Diagram showing inflamed airway with mucus and narrowing compared to improved airway with clearer airflow and better lung function

Can Lung Function Improve After Infection or Treatment?

Diagram showing inflamed airway with mucus and narrowing compared to improved airway with clearer airflow and better lung function
Airways can become narrowed by inflammation and mucus after infection or treatment. With time and the right support, airflow can improve and symptoms may ease.

Last reviewed: May 2026
Audience: Patients, carers, and non-specialists


Key Points

  • Lung function often can improve after infections, chemotherapy, or inflammation—but recovery may take weeks to months.
  • A drop in peak flow usually reflects airway narrowing, inflammation, or mucus, not always permanent damage.
  • Normal oxygen levels (e.g. 95–100%) are reassuring and suggest gas exchange is still working well.
  • Symptoms like breathlessness and wheeze can persist even while the lungs are gradually recovering.
  • If symptoms are not improving, further assessment may help identify treatable causes.

Contents


Can lung function recover?

In many cases, yes—lung function can improve after a significant illness such as a chest infection, chemotherapy, or inflammation affecting the airways.

However, recovery is often gradual and not always straightforward. It may take:

  • Several weeks after an infection
  • Several months after more severe illness or treatment

It is also common for symptoms to fluctuate during recovery rather than steadily improve.


Why has my lung function dropped?

A reduction in peak flow or increased breathlessness does not always mean permanent damage. Common causes include:

  • Airway inflammation (swelling inside the breathing tubes)
  • Mucus build-up, which can block airflow
  • Airway narrowing or spasm, similar to asthma
  • Post-infectious sensitivity (airways remain irritated after infection)
  • Reduced fitness after illness (deconditioning)

In some patients, conditions such as Allergic Bronchopulmonary Aspergillosis (ABPA) or other airway diseases can contribute to ongoing symptoms.

Important: If oxygen levels remain normal (for example, around 97%), this suggests that the lungs are still transferring oxygen effectively, which is reassuring.


Why does recovery feel slow or “stuck”?

Many people feel frustrated because they are doing everything “right” but not seeing improvement. This is very common.

Possible reasons include:

  • Residual mucus that is difficult to clear
  • Ongoing low-level inflammation
  • Airways that remain sensitive after infection
  • Effects of steroid treatment, especially during dose changes
  • Fatigue and reduced activity levels

Recovery can happen slowly in the background, even when symptoms remain noticeable.


What might help?

Different approaches may support recovery. These should be discussed with your clinical team where appropriate.

1. Airway clearance

  • Regular airway clearance techniques can help remove mucus
  • Some people benefit from devices that assist mucus clearance

2. Breathing techniques

Breathing techniques can help reduce breathlessness and improve control. A more detailed guide is provided below.

3. Gradual activity

  • Slowly increasing activity levels can rebuild strength
  • Pacing is important—avoid pushing too hard too quickly

4. Optimising treatment

  • Ensuring inhaler technique is correct
  • Reviewing whether airway inflammation is fully controlled

Breathing Techniques in Detail

Breathing techniques can help reduce breathlessness, improve airflow, and make breathing feel more controlled—especially when airways are inflamed or narrowed.

They do not treat the underlying condition directly, but they can improve symptoms, confidence, and daily activity.

Pursed-Lip Breathing

What it does: Helps keep airways open for longer during breathing out, reducing air trapping and easing breathlessness.

How to do it:

  1. Breathe in slowly through your nose (about 2 seconds)
  2. Purse your lips (as if whistling)
  3. Breathe out slowly through your lips (about 4 seconds)
  4. Keep the breath out gentle, not forced

When to use it:

  • During breathlessness
  • With activity (e.g. walking, stairs)
  • To regain control of breathing

Tip: Aim for a longer out-breath than in-breath.

Diaphragmatic (Belly) Breathing

What it does: Encourages more efficient breathing using the diaphragm rather than upper chest muscles.

How to do it:

  1. Sit or lie comfortably
  2. Place one hand on your chest, one on your abdomen
  3. Breathe in through your nose and allow your abdomen to rise
  4. Breathe out slowly (through pursed lips if helpful)

Tip: Keep shoulders relaxed and avoid lifting the chest.

Breathing Control (for flare-ups)

  • Pause and rest
  • Breathe slowly through the nose
  • Breathe out gently through relaxed or pursed lips
  • Release tension in shoulders and neck

Helpful positions:

  • Sitting leaning forward with arms supported
  • Standing leaning on a surface

“Blow as You Go”

Use during activity:

  • Breathe in before effort
  • Breathe out during effort (e.g. standing up, climbing)

This helps prevent breath-holding and reduces strain.

Important: These techniques should feel comfortable and controlled. If symptoms worsen, stop and rest.


When might further tests be needed?

If symptoms are persistent, worsening, or not improving as expected, your clinical team may consider:

  • Spirometry (lung function tests)
  • Imaging such as a chest CT scan
  • Assessment for:
    • Airway inflammation
    • Bronchiectasis
    • Fungal-related lung disease

Common Questions

Does a drop in peak flow mean permanent damage?

No. Peak flow mainly reflects how open your airways are and can improve with treatment.

Why do I feel breathless if my oxygen levels are normal?

Breathlessness is often caused by airway narrowing or inefficient breathing, not low oxygen.

Can lungs fully recover?

Some people return to their previous baseline. Others improve significantly but may not reach exactly the same level.


When to seek medical advice

  • Worsening breathlessness
  • Increasing wheeze or chest tightness
  • New or persistent cough
  • Changes in sputum (including blood)
  • No improvement over time

If symptoms suddenly worsen, seek urgent medical attention.


Final Thoughts

A drop in lung function after infection or treatment can feel worrying, but it often reflects treatable airway changes. Improvement is possible, although recovery may take time.

Staying in contact with your healthcare team helps ensure that any ongoing issues are identified and managed appropriately.


References & Further Reading

  • British Thoracic Society (BTS) guidance
  • European Respiratory Society (ERS) patient resources
  • National Aspergillosis Centre patient information

This article is for general information only and does not replace medical advice. Always consult your healthcare team.


Infographic showing causes of weight loss and weakness in aspergillosis including inflammation, reduced appetite, medication effects and muscle loss, with stages of recovery.

Weight Loss and Weakness in Aspergillosis: Why It Happens, How It Feels, and What Helps Recovery

Infographic showing causes of weight loss and weakness in aspergillosis including inflammation, reduced appetite, medication effects and muscle loss, with stages of recovery.
Weight loss and weakness in aspergillosis are usually caused by a combination of inflammation, increased energy use, reduced appetite, and muscle loss. Recovery is often gradual and happens in stages.

Last reviewed: April 2026

Unexpected weight loss and severe weakness are among the most worrying symptoms people report after being diagnosed with aspergillosis. Many describe feeling unlike themselves—physically drained, thinner than they have ever been, and struggling with everyday activities.

This article explains why this happens, what is going on in the body, and what recovery typically looks like.

---

Key Points

  • Weight loss and fatigue are common in aspergillosis, particularly early in the illness or during flare-ups.
  • They are usually caused by a combination of inflammation, increased energy use, reduced appetite, and muscle loss.
  • Medication side effects can contribute but are rarely the main cause.
  • Many people improve over time, but recovery is usually gradual and can take weeks to months.
  • Stabilising weight is often the first important step before regaining strength.

---

Contents

---

Why does aspergillosis cause weight loss?

Weight loss in aspergillosis is rarely due to a single cause. Instead, it is usually the result of several overlapping processes.

1. Increased energy use (hypermetabolism)

When the body is dealing with infection or inflammation, it requires more energy. This is sometimes described as a hypermetabolic state.

  • The immune system is active and consumes energy
  • The body produces inflammatory signals
  • Breathing effort may increase

This means you may be burning more calories than usual—even at rest.

2. Reduced appetite

Many people notice they are eating less, sometimes without realising it. This may be due to:

  • Feeling unwell or fatigued
  • Shortness of breath when eating
  • Changes in appetite driven by inflammation

3. Medication effects

Some treatments can affect appetite or digestion. For example:

  • Antifungal medications such as itraconazole or voriconazole may cause nausea or taste changes
  • Steroids may increase appetite but can also contribute to muscle weakness over time

Medication effects vary widely and are usually only part of the overall picture.

4. Muscle breakdown

During illness, the body may break down muscle to meet energy needs. This can happen quickly, especially if activity levels fall.

This leads to:

  • Loss of strength
  • Reduced stamina
  • A feeling of being “weak” rather than just lighter

5. Underlying lung disease

Many people with aspergillosis also have conditions such as bronchiectasis, asthma, or chronic obstructive pulmonary disease (COPD). These can increase the effort required for breathing and contribute to ongoing energy use.

---

What is happening inside the body?

Several biological processes contribute to weight loss and fatigue:

  • Inflammatory signalling: The immune system releases chemical signals that affect metabolism and appetite
  • Catabolism: The body breaks down tissues (including muscle) to release energy
  • Energy imbalance: More energy is used than consumed

This combination can make weight loss feel rapid and difficult to control.

---

Which types of aspergillosis are affected?

These symptoms are most commonly seen in:

However, not everyone experiences weight loss, and severity varies.

---

Why does it feel so severe?

Many people describe this stage as one of the most difficult parts of their illness. This is because several factors are happening at once:

  • Physical energy is reduced
  • Muscle strength has declined
  • The body is under ongoing stress
  • Recovery has not yet begun

This can make everyday activities—such as walking, cooking, or even eating—feel unusually difficult.

---

Does it get better?

In many cases, yes—there is gradual improvement over time, especially once treatment begins to control the condition.

Recovery often follows a pattern:

  • Initial phase: weight loss and severe fatigue
  • Stabilisation: weight loss slows or stops
  • Recovery: gradual return of strength and energy

This process is usually slow and uneven, with good and bad days.

---

What can help day to day?

1. Focus on maintaining nutrition

  • Eat small amounts regularly rather than large meals
  • Choose foods that are easy to prepare and eat
  • Include protein to support muscle maintenance

2. Pace activity carefully

  • Gentle movement can help maintain strength
  • Avoid pushing too hard, as this can worsen fatigue
  • Increase activity gradually as energy improves

3. Look at trends over time

It can be helpful to focus on gradual changes such as:

  • Weight stabilising
  • Small improvements in energy

---

Nutrition and rebuilding strength

Recovery often happens in stages:

  • Stage 1: Stabilising weight
  • Stage 2: Gradually increasing intake
  • Stage 3: Rebuilding muscle and strength

Regaining muscle mass takes time and usually follows once the underlying condition is better controlled.

---

When to seek medical advice

You should contact your healthcare team if you experience:

  • Continued or rapid weight loss
  • Increasing weakness
  • Difficulty eating or swallowing
  • New or worsening symptoms

This may indicate the need for additional support or adjustment of treatment.

---

Common questions

Is weight loss just due to poor appetite?

No. Reduced appetite is only one factor. Increased energy use and muscle loss are also important contributors.

Are medications the main cause?

Medications can contribute, but they are rarely the main reason for weight loss.

Will I regain my strength?

Many people do regain strength over time, although recovery is usually gradual.

Why does recovery take so long?

The body needs time to reduce inflammation, restore energy balance, and rebuild muscle.

---

Summary

Weight loss and weakness in aspergillosis are common and can feel severe, particularly early in the illness. They are usually caused by a combination of increased energy use, reduced appetite, muscle loss, and underlying lung disease.

Although recovery can take time, many people improve gradually as treatment takes effect.

---

Further Reading

---

Author & Review

Prepared for aspergillosis.org to support patient understanding. Content reflects current clinical knowledge and patient-reported experience.

Disclaimer

This page is for general information only and does not replace advice from your healthcare team.


Fermented foods gut lung axis diagram showing microbiome, lungs, reflux and aspiration risks in chronic lung disease

Fermented Foods & Lung Health: Safety, Infection Risk and Aspergillosis

Last reviewed: April 2026

Many people with lung conditions ask whether foods like kefir, yoghurt or cider vinegar could trigger infections. This article explains what we know — and what we don’t — based on current evidence and patient experience.


 

Fermented foods gut lung axis diagram showing microbiome, lungs, reflux and aspiration risks in chronic lung disease
How fermented foods may influence health: most effects are indirect, via the gut–lung axis, reflux, or aspiration rather than direct lung infection

Can fermented foods cause lung infections?

No. There is no strong evidence that fermented foods cause lung infections such as pneumonia. Any effects on the lungs are more likely indirect, for example through reflux or aspiration rather than direct infection.

Quick answer: fermented foods are generally safe, but individual responses vary.


Key Points

  • Fermented foods contain live microorganisms, usually beneficial bacteria and yeasts
  • For most people, these foods are safe and part of a healthy diet
  • There is no strong evidence linking fermented foods to lung infections
  • Some people with lung disease may be affected by reflux or aspiration
  • If symptoms worsen after certain foods, it is reasonable to avoid them

Table of Contents


What are fermented foods?

Fermented foods are made using microorganisms (such as bacteria or yeast) to transform food. Examples include yoghurt, kefir, sauerkraut, kimchi, cheese and cider vinegar (including those containing the “mother”).

These microorganisms are generally considered non-harmful or beneficial.


Are fermented foods safe?

For most people, including many with chronic lung conditions, fermented foods are considered safe.

They may support gut health, although evidence varies depending on the product and individual.

You can read more in our

diet and aspergillosis guide
.


Can they cause infections?

There is no clear evidence that eating fermented foods causes lung infections such as pneumonia.

Lung infections usually arise from:

  • Microorganisms already present in the airways
  • Inhaled organisms from the environment

This is explored further in our article:

Why antibiotics do not always work
.


Why do concerns arise in lung conditions?

People with aspergillosis, bronchiectasis or chronic lung disease may be more sensitive to changes affecting the lungs.

1. Aspiration

If small amounts of food or liquid enter the airway, this can contribute to infection.

2. Reflux

Reflux can reach the upper airway and may play a role in lung irritation.

3. Lung microbiome

The lungs contain their own microbial environment, which can shift during illness.

4. Coincidence vs causation

An infection occurring after a dietary change does not necessarily mean the food caused it.

Evidence in this area is still developing, and most studies focus on gut health rather than direct lung effects.


Who might need to be more cautious?

  • Frequent lung infections
  • Significant bronchiectasis
  • Swallowing difficulties
  • Severe reflux
  • Weakened immune systems

At specialist centres such as the National Aspergillosis Centre, these factors are considered alongside overall lung health.


Practical considerations

  • Avoid foods that appear to worsen symptoms
  • Introduce new foods gradually
  • Be cautious with unpasteurised products
  • Keep a simple symptom diary

Common questions

Are probiotics the same as fermented foods?

No. Probiotics are specific strains studied for health benefits, while fermented foods vary widely.

Should people with aspergillosis avoid fermented foods?

There is no general recommendation to avoid them. Most people tolerate them well.

Can fermented foods affect the lungs directly?

Not usually. Effects, if present, are more likely indirect.


When to seek medical advice

  • New or worsening breathlessness
  • Persistent cough or sputum changes
  • Fever or infection symptoms
  • Repeated infections

Summary

Fermented foods are generally safe, but individual responses vary. There is no strong evidence linking them to lung infections, but factors such as reflux or aspiration may be relevant in some people.

Balancing general evidence with personal experience is key.


References


Author & Review

This article has been prepared by the National Aspergillosis Centre CARES team for patients and non-specialists.

It is intended for general education and should not replace individual medical advice.



Help us understand how damp homes affect health

We are supporting a UK research project looking at how damp homes may affect health, including respiratory health and conditions such as aspergillosis.

This study is being led by the National Aspergillosis Centre at Manchester University NHS Foundation Trust, and is being shared through aspergillosis.org to support research into damp homes and health.

We are currently inviting people across the UK to register their interest in taking part.

Registering your interest should take less than one minute and does not commit you to taking part.


Register your interest now

Why this matters

Damp and mould are often linked to health problems, but there is still limited real-world evidence from people’s homes across the UK.

This project aims to help improve understanding of how home environments may affect health by gathering information from people living in a wide range of housing conditions.

Who can register interest?

We would like to hear from people living in the UK, including:

  • people with lung or respiratory conditions
  • people without any known lung or breathing condition
  • people who have experienced damp or mould at home
  • people who have not experienced damp or mould at home
  • members of the general public who would like to contribute to the research

We are keen to hear from people with different health backgrounds and a wide range of home environments.

What is the study about?

This research is exploring how damp homes may affect health. The aim is to improve understanding of the relationship between home environments and health symptoms in real-world settings.

This project is for research purposes only and does not provide medical advice or diagnosis.

What might taking part involve later?

If the study opens, some people who register interest may later be invited to:

  • complete a short questionnaire about their home and health symptoms
  • receive a simple home sampling kit by post
  • collect and return a small household sample, for example dust from the home, for research purposes

The home sampling part is intended to be simple and practical. Full instructions would be provided.

Registering your interest now does not commit you to taking part later.

Important information

  • Registering interest is voluntary.
  • You do not have to take part in the full study later.
  • Your details will only be used to contact you about this project.
  • Your data will be handled in line with UK data protection regulations.
  • You can decide later whether or not to take part.

Frequently asked questions

Am I signing up to take part in the study now?

No. At this stage, you are only registering your interest in hearing more about the study.

Do I need to have a lung condition to register interest?

No. We would like to hear from people with and without lung conditions.

Do I need to have damp or mould in my home?

No. We are interested in hearing from people with a wide range of home environments and experiences.

Will I definitely receive a kit?

Not necessarily. Registering interest helps the research team understand the level of interest and contact people if the study opens.

Will I get personal results about my home or health?

At this stage, no individual results are being promised. More information would be provided if the study proceeds.

What happens after I register interest?

You do not need to do anything further straight away. If the study opens, you may be contacted with more information so you can decide whether you would like to take part.

Register your interest

Ready to help? Complete the form below.

This secure form should take less than one minute to complete.

If the form does not load, you can open it here:

Open the form in a new window


Kefir and aspergillosis infographic

Can People with Aspergillosis Drink Kefir or Take Probiotics?

Many people with aspergillosis ask whether they can safely drink kefir or take probiotics. Kefir is a fermented drink containing live bacteria and yeasts, which raises understandable questions for people with lung conditions. This article explains what is known, what is uncertain, and why advice can differ between chronic pulmonary aspergillosis (CPA), allergic bronchopulmonary aspergillosis (ABPA), and more severe forms of aspergillosis.

Short answer: this is not something with a simple yes-or-no answer. For people with chronic forms of aspergillosis, kefir and probiotic products are not routinely discussed in the same way as they are for people who are severely immunocompromised. However, there is also not enough evidence to say they are helpful for aspergillosis, and people’s experiences vary.


Key Points

  • Advice about live foods is often stricter for people with invasive aspergillosis or severe immune suppression
  • For chronic pulmonary aspergillosis (CPA), allergic bronchopulmonary aspergillosis (ABPA), and related long-term conditions, the picture is usually less clear-cut
  • There is no strong evidence that kefir specifically helps or harms chronic aspergillosis
  • Some people feel fine with fermented foods; others feel they do not suit them
  • The aim here is to inform, not recommend

What Is Kefir?

Kefir is a fermented drink, usually made from milk, containing a mixture of bacteria and yeasts. It is often described as a probiotic food because it contains live microorganisms.

People may use kefir or probiotic products because of interest in:

  • gut health
  • recovery after antibiotics
  • the microbiome

If you are interested in the wider role of food and nutrition in lung health, see our article on diet and aspergillosis: what helps, what doesn’t, and what matters most.


Why Does This Question Come Up in Aspergillosis?

Different forms of aspergillosis have different risk profiles

It is important not to group all forms of aspergillosis together.

  • Invasive aspergillosis usually affects people with very weakened immune systems. In that setting, clinicians are often more cautious about foods or products containing live microorganisms.
  • Chronic pulmonary aspergillosis (CPA) usually affects people with underlying lung damage or structural lung disease. Many patients are not severely immunocompromised in the same way.
  • Allergic bronchopulmonary aspergillosis (ABPA) and related allergic conditions raise slightly different questions again, because symptom flares may relate more to sensitivity and inflammation than to infection risk.

That distinction matters, because advice that is appropriate for one group may not automatically apply to another.


Chronic vs Invasive Aspergillosis: Why It Matters

For people with chronic pulmonary aspergillosis, the question is usually less about needing to avoid kefir as a rule, and more about recognising that there is no established role for it in treatment. In other words, kefir is not a treatment for CPA, but nor is it routinely listed as something that every patient with CPA must avoid.

For people with ABPA, the picture is slightly different again. Some patients are very aware of foods that seem to trigger symptoms, but that still does not create a universal rule that fermented foods should always be avoided.


What Does the Evidence Say?

At present, there is no strong evidence showing that kefir has a specific benefit for aspergillosis, and there is also no clear evidence that it is harmful in most people with chronic aspergillosis.

Most discussion around kefir and probiotics comes from broader research on:

  • the gut microbiome
  • antibiotic-associated bowel symptoms
  • general digestive health

That is not the same as proving benefit for lung symptoms, fungal disease, or long-term respiratory outcomes.

For related discussion about how antibiotics affect symptoms, infections, and the microbiome, you may also find this helpful: why antibiotics do not always work.


Probiotics and the Gut–Lung Connection

Research into the gut–lung axis suggests that the gut microbiome may influence immune responses elsewhere in the body, including the lungs. This is an active area of research, but it is still early, and it does not yet mean that fermented foods or probiotic supplements should be seen as treatments for aspergillosis.

Some people are interested in probiotics because of repeated antibiotic courses, bowel side effects, or a general wish to support gut health. Those are understandable reasons, but the evidence for a direct lung benefit in chronic aspergillosis remains limited.


Why Do People React Differently?

The main reasons for caution are usually not “aspergillosis” on its own, but the wider clinical picture.

For example, extra caution may be more relevant in people who are:

  • severely immunocompromised
  • taking high-dose steroids or other immunosuppressive treatment
  • acutely unwell
  • known to react poorly to fermented foods or probiotic products

In some people, symptoms after kefir may be more about tolerance than infection risk. Patients sometimes describe:

  • bloating
  • nausea
  • abdominal discomfort
  • a sense that fermented foods do not suit them

Others report no obvious problems at all. This is one reason it is safer to frame kefir as an individual tolerance issue rather than something routinely recommended or routinely banned.


Kefir in Chronic Pulmonary Aspergillosis (CPA)

For people with CPA, the question is usually less about fungal exposure from kefir and more about whether it suits the individual patient. Many people with CPA have damaged lungs rather than profound immune suppression, so the same dietary warnings used in invasive fungal disease do not automatically apply.

  • kefir is not a standard treatment for CPA
  • it is not routinely listed as something that must be avoided in all patients with CPA
  • individual circumstances, treatments, and tolerance still matter

If you are newly diagnosed or want a broader overview, see our CPA information page.


What About ABPA and Other Allergic Conditions?

In ABPA and related conditions, some people are understandably more alert to foods that seem to trigger symptoms. Fermented products may not suit everyone, but there is not a clear universal rule that they should be avoided.

As with many food-related questions in chronic lung disease, experiences are mixed and difficult to generalise. If you would like a fuller explanation of ABPA itself, visit our ABPA information page.


Homemade vs Shop-Bought Products

Some people also ask whether homemade kefir is different from commercial products. In general terms, homemade fermented products may be less standardised than commercially prepared ones, but that does not automatically mean they will cause a problem. It simply adds another layer of variability.

This is another reason why broad, one-size-fits-all advice is difficult.


How Should This Be Framed for Patients?

A cautious and balanced way to put it is:

Kefir is a fermented drink containing live bacteria and yeasts. Questions about it often come up in aspergillosis because advice is sometimes stricter for people who are severely immunocompromised. For people with chronic conditions such as CPA or ABPA, there is no clear evidence that kefir is either beneficial or harmful for aspergillosis itself. People’s experiences vary, so it is best thought of as an individual tolerance issue rather than something routinely recommended or routinely banned.


When Extra Caution May Be Needed

Extra caution may be more relevant if someone is:

  • severely immunocompromised
  • on significant immunosuppressive treatment
  • recovering from serious illness
  • already experiencing ongoing gut symptoms or unexplained food intolerance

In those situations, questions about probiotics, supplements, or fermented foods are often best discussed with a clinician who understands the wider medical picture.


When to Seek Medical Advice

It is sensible to discuss diet or probiotic questions with a clinician or specialist team if:

  • you are severely immunocompromised
  • you are on significant immunosuppressive treatment
  • you develop persistent gut symptoms after using a probiotic product
  • you are unsure how advice applies to your particular diagnosis or treatment

Healthcare professionals looking for more formal clinical material can visit our Information for Professionals page.


Common Questions

Can kefir treat aspergillosis?

No. There is no evidence that kefir treats aspergillosis.

Is kefir dangerous with chronic pulmonary aspergillosis?

There is no clear evidence that kefir is harmful in most people with chronic pulmonary aspergillosis, but there is also no evidence that it is beneficial for the condition itself. Tolerance varies between individuals.

Should people with ABPA avoid fermented foods?

Not necessarily. Some people feel certain foods do not suit them, but there is no universal rule that all fermented foods should be avoided in ABPA.


Summary

  • Kefir is a fermented probiotic drink containing live bacteria and yeasts
  • Advice that applies to invasive aspergillosis does not always apply in the same way to chronic pulmonary aspergillosis or allergic bronchopulmonary aspergillosis
  • There is no strong evidence that kefir treats or worsens chronic aspergillosis
  • The safest educational position is a neutral one: not a recommendation, not a blanket prohibition
  • Individual circumstances, treatments, and tolerance matter

Last reviewed: April 2026
Reviewed by: National Aspergillosis Centre patient information team perspective
Please note: This article is for general education and should not be used as individual medical advice.


What if you can’t tolerate azole antifungal medicines?

Last reviewed: April 2026


Key points

  • Azole antifungals are commonly used to treat aspergillosis, but not everyone tolerates them well.
  • “Azole intolerance” means the body reacts badly to the medication, even if it is otherwise effective.
  • Symptoms can include fatigue, flushing, shaking, nausea, and discomfort around the liver area.
  • In some cases, blood tests show changes in liver function.
  • If azoles are not tolerated, there are often alternative approaches your clinical team can consider.

Contents


What are azole antifungals?

Azole antifungals are a group of medicines used to treat fungal infections such as aspergillosis. They work by interfering with the fungal cell membrane, helping to stop the fungus growing.

Common examples include:

  • Fluconazole
  • Itraconazole
  • Voriconazole
  • Posaconazole

They are often used long-term in conditions like chronic pulmonary aspergillosis (CPA) or allergic bronchopulmonary aspergillosis (ABPA).


What is azole intolerance?

Azole intolerance means that a person develops unpleasant or harmful side effects when taking these medications, even at standard doses.

This is different from:

  • Allergy – an immune reaction (e.g. rash, swelling, breathing difficulty)
  • Resistance – when the fungus is not affected by the drug

With intolerance, the drug may still work against the fungus—but the body cannot tolerate its effects.


Why does azole intolerance happen?

There is no single cause. Instead, several factors can contribute:

1. How the body processes the drug

Azoles are broken down in the liver. People vary in how efficiently this happens, which can lead to higher levels of the drug in the body.

2. Effects on liver enzymes

Azoles affect enzymes (called cytochrome P450 enzymes) that are involved in processing many medications. This can:

  • Increase drug levels
  • Cause interactions with other medications
  • Put strain on the liver

3. Individual sensitivity

Some people are simply more sensitive to these drugs, even when blood levels are within the expected range.

4. Other health factors

  • Existing liver conditions
  • Age
  • Other medications
  • Nutritional status

Common symptoms to look out for

Patients describe a range of symptoms when azoles are not well tolerated, including:

  • Flushed or hot cheeks
  • Shaking or tremor
  • Severe fatigue
  • Nausea or reduced appetite
  • Discomfort or pain in the upper abdomen, back, or sides (where the liver sits)
  • General feeling of being unwell

These symptoms can appear soon after starting treatment or develop over time.


The role of the liver

The liver plays a central role in processing azole antifungals.

In some cases, this can lead to:

  • Raised liver enzymes on blood tests
  • Inflammation or irritation of the liver

It is important to note that:

  • Some people have abnormal blood tests without symptoms
  • Others feel unwell even when tests are only mildly changed

This is why both symptoms and blood tests are considered together.


What can be done if azoles are not tolerated?

If azole intolerance is suspected, your clinical team may consider several approaches:

Adjusting treatment

  • Reducing the dose
  • Changing how the medication is taken (e.g. with food)

Switching to another azole

Some people tolerate one azole better than another.

Therapeutic drug monitoring (TDM)

Blood tests can measure drug levels to help ensure they are not too high or too low.

Considering non-azole treatments

In some cases, different classes of antifungal medication may be considered.

The best approach depends on the individual, the condition being treated, and how severe the side effects are.


Why monitoring is important

Because azoles affect the liver and interact with other medications, monitoring is a routine part of care.

This may include:

  • Regular liver function blood tests
  • Drug level monitoring (for some azoles)
  • Review of other medications

Monitoring helps detect problems early and allows treatment to be adjusted safely.


Common questions

Does intolerance mean I cannot take any antifungal treatment?

No. Many patients who cannot tolerate one medication can use another, or a different approach may be possible.

Will the symptoms settle if I continue?

In some cases mild symptoms improve, but persistent or worsening symptoms should always be reviewed.

Is this common?

Most people tolerate azoles reasonably well, but intolerance is recognised and not rare in specialist clinics.


When to seek medical advice

You should contact your healthcare team if you experience:

  • Persistent or worsening fatigue
  • Pain in the upper abdomen, back, or sides
  • Nausea affecting eating or drinking
  • New or unusual symptoms after starting medication

Seek urgent medical attention if you notice:

  • Yellowing of the skin or eyes (jaundice)
  • Dark urine or pale stools
  • Severe abdominal pain

Summary

Azole antifungals are an important part of treating aspergillosis, but some people experience intolerance.

This is usually related to how the body processes the medication—particularly in the liver—and varies from person to person.

If intolerance occurs, it does not mean that treatment options have run out. With careful monitoring and specialist input, alternative strategies can often be found.


Further reading


Author & review

This article has been prepared for patients and carers using information aligned with UK specialist practice, including the National Aspergillosis Centre (Manchester, UK).

Important: This content is for general educational purposes only and is not a substitute for medical advice. Always speak to your healthcare team about your own situation.


Allergy, Intolerance and Wheat Reactions: What Is Actually Going On?

Key points

  • You can have real and sometimes severe symptoms without having a classic allergy.
  • Allergy, intolerance, and non-IgE reactions involve different biological pathways.
  • Similar symptoms (such as wheeze or mucus) do not always mean the same cause.
  • The term “intolerance” is often used as a catch-all, which can be confusing.
  • For people with lung conditions, triggers may still worsen symptoms even when allergy tests are negative.

This article is general educational information for patients and carers. If you are new to this topic, you may wish to start with our overview of what is aspergillosis or explore common symptoms affecting the lungs and airways.

Contents

Why this is so confusing

Many people use the word “allergy” to describe any reaction to food or environmental triggers. This is understandable, because the symptoms can feel very similar.

For example:

However, similar symptoms do not always mean the same biological cause. This is where confusion begins.

What is a true allergy?

A true allergy usually refers to an IgE-mediated immune reaction.

This means the immune system reacts quickly to a substance, often within minutes to a couple of hours. Symptoms may include:

This type of reaction is what most allergy clinics are designed to detect, because it can be serious and is usually testable.

What is an intolerance?

An intolerance is a broader term used when symptoms do not follow the classic IgE allergy pathway.

It may involve:

  • digestive processes
  • food chemicals such as histamine or salicylates
  • gut–immune interactions
  • non-specific inflammation

Importantly: intolerance does not mean “mild” or “unimportant”. It simply means the mechanism is different and often harder to measure.

For guidance on managing food-related symptoms, see our diet and nutrition hub.

The grey area: non-IgE reactions

Not all immune reactions involve IgE.

Some reactions involve other parts of the immune system and may be:

  • delayed
  • longer lasting
  • harder to detect with standard tests

This creates a grey area between “allergy” and “intolerance”.

This is why the statement:

“Same symptoms but no IgE = intolerance”

is often an oversimplification.

Wheat as an example

Wheat reactions are often used to illustrate this complexity:

  • Wheat allergy → IgE reaction to wheat proteins
  • Coeliac disease → autoimmune condition (see NICE guidance)
  • Non-coeliac wheat sensitivity → unclear mechanism
  • Carbohydrate intolerance → reaction to fructans (FODMAPs)

All of these may cause symptoms, but they require different ways of understanding and managing.

Why “downgraded” feels upsetting

Patients are sometimes told they have been “downgraded” from allergy to intolerance.

In reality, what has usually happened is:

  • a classic IgE allergy has been considered unlikely
  • testing is unlikely to add further information
  • the reaction falls into a less clearly defined category

This is a change in classification, not a judgement about importance or severity.

Why this matters in asthma and aspergillosis

For people with asthma, Allergic Bronchopulmonary Aspergillosis (ABPA), or chronic pulmonary aspergillosis (CPA):

  • airways are often more sensitive
  • inflammation may already be present

This means that triggers do not always need to be classic allergens to cause problems.

Symptoms such as wheeze, mucus and chest tightness may worsen even when allergy tests are negative.

You may also find it helpful to read why antibiotics do not always work, which explains how non-bacterial causes can drive ongoing symptoms.

Why testing is often limited

Allergy testing works best for IgE-mediated conditions.

For many other reactions:

  • there are no simple validated tests
  • diagnosis relies more on clinical history and patterns

Further detail for clinicians and advanced readers is available in our information section for patients.

What usually happens next?

After a classic allergy has been ruled out, the process does not stop—it changes direction.

Understanding patterns

The focus often shifts to identifying:

  • what triggers symptoms
  • how quickly symptoms occur
  • whether effects are delayed or cumulative

Identifying the main system involved

  • Gut-related → bloating, pain, bowel symptoms
  • Airway-related → wheeze, mucus, chest tightness
  • Mixed/systemic → fatigue and general symptoms

Different types of support

Depending on the pattern, support may involve:

This stage is often less clear-cut but can still lead to meaningful improvements over time.

Take-home message

  • Allergy and intolerance are not the same.
  • “Intolerance” is often used as a broad label.
  • Symptoms may be similar, but the underlying pathways differ.
  • This affects how conditions are understood and managed.
  • Even without a clear label, symptoms remain real and important.

When to seek medical advice

Seek urgent help if you develop:

  • sudden breathing difficulty
  • swelling of the lips, tongue or throat
  • collapse or severe dizziness

Arrange medical review if you have:

  • persistent or worsening symptoms
  • repeated reactions to foods or triggers
  • worsening respiratory symptoms

Related topics

References

  1. NHS – Food allergy and intolerance
  2. BSACI – Food allergy guidance
  3. NICE NG20 – Coeliac disease

Last reviewed: April 2026

Author: Aspergillosis Website Team

Review status: Educational content for patients and carers


Inflammation and Aspergillosis: Understanding “Stable”, “Flare”, and “Improving” Disease

Last reviewed: April 2026

Key points

  • Inflammation is part of the body’s response to Aspergillus, but it does not always mean damage is actively worsening.
  • “Stable” disease means no clear progression over time, not that the condition has disappeared.
  • Symptoms in aspergillosis often vary because of other infections, especially in the lungs.
  • Test results (such as IgE or CRP) can change without symptoms changing.
  • Doctors make decisions based on the overall pattern over time, not a single test result.

Table of contents


What is inflammation and why does it matter?

Inflammation is the body’s way of responding to something it sees as harmful. In aspergillosis, this is usually the fungus Aspergillus.

This response involves immune cells, chemicals, and changes in the lungs that aim to control the fungus. However, if inflammation continues over a long period (chronic inflammation), it can also contribute to:

  • Ongoing symptoms (cough, breathlessness, fatigue)
  • Mucus production
  • Damage to lung tissue over time

Important: inflammation can be present at a low level without causing active damage. This is common in chronic conditions.


Inflammation in different types of aspergillosis

The type of inflammation depends on the form of aspergillosis:

  • Allergic Bronchopulmonary Aspergillosis (ABPA): driven by an overactive allergic response. Blood markers such as IgE and eosinophils are often used to monitor this.
  • Chronic Pulmonary Aspergillosis (CPA): caused by long-term infection in damaged lung tissue, leading to ongoing inflammation and structural changes.
  • Aspergillus bronchitis: persistent infection with inflammation, often causing chronic cough and sputum.

In all cases, inflammation may improve with treatment but often does not disappear completely.


Clear definitions: disease states

Doctors use the following terms to describe how the disease is behaving:

  • Active disease: symptoms, tests, or scans are getting worse over time
  • Flare-up: a short-term worsening, often triggered by infection or another stress on the body
  • Stable: no clear overall change over time
  • Improving / responding to treatment: symptoms and/or tests are getting better
  • Remission: minimal or no signs of active disease (used more often in ABPA)

Key point: these states are not fixed — patients may move between them.


What does “stable disease” mean in practice?

“Stable” means that, over a period of time (weeks to months), there is no clear evidence that the disease is progressing.

This usually includes:

  • No worsening of key symptoms
  • No new complications (e.g. haemoptysis, significant weight loss)
  • Imaging (CT scans) showing no progression
  • No need to increase treatment

What stable does NOT mean:

  • It does not mean symptoms are absent
  • It does not mean inflammation is zero
  • It does not mean you will feel the same every day

Many patients with stable disease still experience day-to-day variation in symptoms.


Why other infections cause flare-ups

People with aspergillosis are more vulnerable to other lung infections (bacterial or viral).

This is because:

  • Lung structure may already be damaged
  • Mucus clearance is less effective
  • The immune system is already active

When another infection occurs, it can trigger a flare-up, causing:

  • Increased cough and breathlessness
  • More or thicker sputum
  • Fatigue and feeling unwell
  • Raised inflammatory markers (e.g. CRP)

Crucial point: this does not necessarily mean the aspergillosis itself is worsening. It is often a temporary additional problem.


Understanding test results

Doctors use several types of tests to monitor inflammation and disease activity:

  • CRP / ESR: general markers of inflammation
  • IgE: particularly important in ABPA
  • Eosinophils: linked to allergic inflammation
  • CT scans: show structural changes in the lungs
  • Sputum cultures: detect infection

Important limitations:

  • No single test gives a complete picture
  • Results can fluctuate for many reasons
  • Changes must be interpreted over time

When test results worsen but symptoms do not

This situation is common, especially in ABPA.

For example, IgE levels may rise without any noticeable change in symptoms.

This may happen because of:

  • Natural biological variation
  • Exposure to allergens
  • A mild or early flare that has not yet caused symptoms

Key point: a change in a single test result does not automatically mean the disease is worsening.

Doctors will usually:

  • Repeat tests
  • Look for consistent trends
  • Assess symptoms and scans

If symptoms remain stable and no other changes are seen, the condition may still be considered stable — but monitored more closely.


How doctors decide what is happening

Clinicians do not rely on a single result. Instead, they assess the pattern over time:

  • Are symptoms changing?
  • Are test results consistently rising or falling?
  • Are scans stable or changing?
  • Is the patient responding to treatment?

This combined assessment is called the clinical picture.


Common questions

If I feel better, what is that called?

This is usually described as improving or responding to treatment. In some cases (especially ABPA), it may be called remission.

Does inflammation always mean damage?

No. Low-level inflammation can persist without causing further harm.

Why do my symptoms change from day to day?

This is common and often relates to infections, environment, or general health rather than disease progression.

Can aspergillosis affect the whole body?

It can have wider effects, but it mainly affects the lungs in most patients.


When to seek medical advice

Seek medical advice if you notice:

  • Persistent worsening of symptoms
  • New haemoptysis (coughing up blood)
  • Significant weight loss
  • Symptoms not improving after a suspected infection
  • Concerns about test results

Author and review

Author: Aspergillosis Patient Education Team
Reviewed by: National Aspergillosis Centre (UK)


References

  • Denning DW et al. Chronic pulmonary aspergillosis guidelines
  • ISHAM ABPA guidelines

This article is for general information only and is not a substitute for medical advice.


Aspergillosis and Diet: coping with weight loss, poor appetite, food avoidance and stomach symptoms

For: patients, carers, general practitioners, specialist nurses and other non-specialists


Key points

  • Eating difficulties are common in aspergillosis, especially in chronic pulmonary aspergillosis (CPA) and in people who also have other lung disease.
  • The problem is often not simply “poor appetite”. Breathlessness, cough, fatigue, reflux, nausea, altered taste and medicine side effects can all make eating difficult.
  • Some people gradually cut out more and more foods because eating feels uncomfortable or because they have been told certain foods are “bad” for lung symptoms.
  • For many patients, the main nutritional goal is not a “perfect” diet. It is getting enough energy, protein and fluids in ways that feel manageable.
  • “Little and often”, food fortification and nourishing drinks are often more realistic than trying to eat three large meals a day.
  • Ongoing weight loss, a very restricted diet, persistent nausea, reflux or difficulty eating most days should be discussed with a doctor, specialist team or dietitian.


Why diet can become a major problem in aspergillosis

Many people living with aspergillosis find that eating becomes much harder than it used to be. This is particularly important in chronic pulmonary aspergillosis (CPA), where weight loss, fatigue and general ill health are common features of the illness. In practical terms, the body may need more energy while the person is less able to eat comfortably.

Several problems can overlap:

  • Breathing takes more effort, which can increase energy needs.
  • Coughing or breathlessness can interrupt meals.
  • Tiredness can make shopping, cooking and eating feel like hard work.
  • Inflammation and chronic illness can reduce appetite and contribute to muscle loss.
  • Antifungal treatment and other medicines can cause nausea, altered taste, indigestion or poor appetite.
  • Reflux, bloating or early fullness may mean that even small meals feel uncomfortable.

For some patients this creates a vicious circle: eating becomes unpleasant, intake falls, weight drops, strength falls, and eating may then feel even more difficult.

Who is most affected?

Not every patient with aspergillosis has major nutritional problems, but some groups are more likely to struggle. This includes people with:

  • Chronic pulmonary aspergillosis (CPA)
  • pre-existing lung disease such as chronic obstructive pulmonary disease (COPD), bronchiectasis or previous tuberculosis
  • long-term fatigue, breathlessness or coughing
  • persistent nausea or reflux symptoms
  • a history of recent unplanned weight loss
  • side effects from antifungal or other medicines
  • anxiety around eating because meals repeatedly trigger symptoms

Some people with allergic bronchopulmonary aspergillosis (ABPA) also report poor intake or nutritional difficulties, although the pattern may differ from CPA. In ABPA, steroid treatment, asthma burden, medicine effects and general symptom load may all influence diet.

How eating can become difficult

People often describe eating problems in ways that do not sound like a classic “nutrition” issue. They may say things like:

  • “I get full after a few mouthfuls.”
  • “I cannot face a proper meal.”
  • “Eating makes me cough.”
  • “I feel uncomfortable after food.”
  • “Some foods seem to sit badly.”
  • “I only eat a few safe foods now.”

These experiences are important. They suggest that the real problem may be a mixture of breathlessness, upper gastrointestinal symptoms, medicine effects and learned food avoidance, not simply a lack of willpower or poor food choices.

When eating shrinks into a “minimal diet”

Some patients end up eating very little, often because that feels safer or more manageable than trying to eat normally. A “minimal diet” may look like:

  • very small amounts of food only once or twice a day
  • mostly soft or liquid foods
  • reliance on tea, toast, soup or yoghurt
  • long gaps without eating
  • skipping meals because eating feels exhausting

This is understandable, but it can become a serious problem. Small intake over time may lead to:

  • weight loss
  • loss of muscle mass
  • greater weakness and fatigue
  • slower recovery from illness
  • reduced ability to cope with infections or treatment

If a patient is managing only tiny amounts of food, the first goal is often not to rebuild a “normal” diet immediately. It is to make intake easier, more comfortable and more nourishing.

Avoiding many food types

Another common pattern is gradual food restriction. Patients may stop eating several food groups because they believe these foods worsen mucus, cough, reflux, nausea or fungal disease.

Examples include avoiding:

  • dairy products
  • sweet foods
  • bread or dry foods
  • meat
  • acidic foods
  • foods linked in the mind to a previous bad episode

Sometimes there is a genuine reason for avoiding a particular food. For example, reflux may make acidic or very fatty foods uncomfortable, and a dry crumbly food may clearly trigger coughing. The difficulty is that repeated bad experiences can also lead to over-restriction, where more and more foods are cut out than is really necessary.

That can leave the diet low in calories, low in protein and very repetitive. In practice, the aim is usually to adapt foods rather than cut out whole food groups unless there is a clear reason to avoid them.

Could the stomach or gut be part of the problem?

Yes. This is often overlooked.

Some patients with aspergillosis describe symptoms that sound mainly digestive rather than respiratory, for example:

  • nausea
  • heartburn or reflux
  • bloating
  • feeling full very quickly
  • upper abdominal discomfort
  • reduced appetite after starting or changing medication
  • alternating diarrhoea and constipation

There are several possible reasons:

  • Medicine side effects, including antifungals
  • Gastro-oesophageal reflux disease (GORD), which can also worsen cough
  • reduced activity levels and chronic illness
  • constipation, especially when intake is poor or medicines contribute
  • co-existing gastrointestinal disease that is separate from aspergillosis

If eating repeatedly causes upper abdominal or chest discomfort, or if reflux and nausea are prominent, it is reasonable to think of this as a symptom needing review rather than simply a “fussy eating” problem.

Practical ways to make eating easier

Different things help different people, but these approaches are often more realistic than trying to push through large meals.

1. Think “little and often”

Many people do better with five or six small eating opportunities through the day instead of three big meals. That may mean a small breakfast, a mid-morning snack, a light lunch, a nourishing drink, an evening meal and a supper snack.

2. Lower the effort of eating

Soft, moist foods are often easier than dry, chewy or crumbly foods. Examples include:

  • porridge
  • yoghurt
  • custard or rice pudding
  • mashed potato with added butter or cheese
  • scrambled eggs
  • soup with cream or grated cheese
  • stews, casseroles or sauced dishes

3. Use drinks as nutrition

For some patients, drinks are easier to manage than food. Nourishing options can include:

  • milky drinks
  • smoothies
  • milkshakes
  • fortified hot drinks
  • commercial oral nutritional supplements if prescribed or advised

4. Rest before eating

If fatigue or breathlessness are major barriers, it can help to eat after a rest rather than after exertion. Some people find breakfast or lunch easier than an evening meal.

5. Sit upright and stay upright afterwards

This can be especially helpful when reflux, coughing or chest discomfort are part of the picture.

6. Slow the pace

It is acceptable to eat slowly and pause often. Some patients benefit from smaller mouthfuls and short breathing pauses between them.

7. Look for manageable variety

If the diet has become very narrow, widening it gently may be more successful than trying to overhaul everything at once.

How to support weight maintenance

When keeping weight on is difficult, the most useful approach is often to increase the energy and protein content of what is already being tolerated.

Food-first ideas

  • Add butter, cream, cheese, yoghurt, milk powder or olive oil to foods where suitable.
  • Choose full-fat products rather than “diet” versions if weight loss is a concern.
  • Add grated cheese to soup, mashed potato, scrambled eggs or vegetables.
  • Make porridge with milk rather than water.
  • Keep easy snacks available, such as yoghurts, cheese and crackers, peanut butter, hummus, custard, rice pudding or milky desserts.

Protein matters

Protein helps preserve muscle. Good sources include:

  • milk, yoghurt and cheese
  • eggs
  • meat, fish and poultry if tolerated
  • beans, lentils and other pulses
  • nut butters where suitable

Oral nutritional supplements

When food alone is not enough, a doctor or dietitian may suggest oral nutritional supplements. These are often used between meals rather than instead of meals. They can be particularly helpful when appetite is low or meal size is very limited.

In general UK nutrition practice, a “food first” approach is usually tried first where appropriate, but oral nutritional supplements are commonly used when someone is at higher risk of malnutrition or is unable to meet needs from food alone.

Food and medicine issues to remember

Food and medicine can interact in two main ways.

1. Medicines can affect eating

Antifungal treatment and other medicines may contribute to:

  • nausea
  • indigestion
  • altered taste
  • poor appetite
  • bowel upset

If these symptoms started after a medicine was introduced or changed, it is worth discussing that with the prescribing team.

2. Food can affect medicines

Some antifungal medicines have specific instructions about when to take them in relation to food. For example:

  • Itraconazole capsules are generally taken with or just after food, while itraconazole liquid is generally taken on an empty stomach.
  • Voriconazole is usually taken on an empty stomach.
  • Some medicines also have important interactions with antacids or acid-suppressing medicines.

Because formulations differ, and because other medicines may also interact, patients should follow the instructions they have been given for their exact preparation and check with a pharmacist or clinical team if unsure.

Grapefruit and other food interactions: some medicines have clinically important food interactions. Patients should check current advice for each medicine rather than relying on memory or online generalisations.

Common diet myths

Dairy always makes mucus worse

This is a very common belief. Current evidence does not show that dairy routinely increases lung mucus production for most people. Some people do notice a thicker mouth or throat feeling after milk, which may relate to texture rather than extra mucus. If dairy is well tolerated, it can be a useful source of calories and protein.

Sugar “feeds” aspergillosis, so it should be cut out completely

Patients often hear this online, but strict self-imposed restriction can be more harmful than helpful when someone is already struggling to maintain intake. For many patients with weight loss, the immediate nutritional priority is adequate calories and protein, not aggressive dietary exclusion.

There is a special anti-aspergillosis diet

There is no widely accepted specialist diet that treats aspergillosis itself. In routine practice, nutrition advice usually focuses on preventing or treating malnutrition, easing symptoms and managing medicine-related issues.

If eating is difficult, I should just avoid more foods

Sometimes a food really is hard to tolerate, but repeated restriction can shrink the diet too far. Often it is more useful to ask, “Can this be made easier to eat?” rather than “Should I cut this out altogether?”

When to seek medical help

Patients should speak to their doctor, specialist team or another qualified healthcare professional if they have any of the following:

  • ongoing unplanned weight loss
  • clothes, rings or dentures becoming looser
  • difficulty eating most days
  • a very narrow diet with only a few “safe” foods
  • persistent nausea, reflux, bloating or abdominal discomfort
  • increasing weakness or fatigue
  • concerns that medicines are worsening appetite or stomach symptoms

It may be appropriate to ask about a dietitian referral, especially if intake has been poor for some time or there are signs of malnutrition.

Seek urgent medical advice if:

  • food or fluids are being kept down very poorly
  • there are signs of dehydration
  • weight loss is rapid or severe
  • pain, vomiting, swallowing difficulty or other worrying symptoms are developing

Common questions

Should I force myself to eat full meals?

Usually not. If full meals are consistently overwhelming, smaller and more frequent intake is often more successful.

Are liquid calories “cheating”?

No. For some people, nourishing drinks are one of the most practical ways to protect weight and strength.

What if I only manage a few foods?

That is still worth discussing. A restricted diet may be understandable, but it can increase nutritional risk over time.

What if dairy feels unpleasant?

Individual experience matters. If a food clearly feels uncomfortable, it may help to try alternatives or use smaller amounts in different forms. But many people do not need to exclude dairy automatically.

Could reflux be making my cough worse?

Yes, it can in some people. Reflux can irritate the upper airway and may contribute to cough or discomfort around meals.

When to seek medical advice

Ask for medical advice if you are losing weight, struggling to eat most days, developing a very restricted diet, or think nausea, reflux or medication side effects are affecting your intake. Ask urgently if you are becoming dehydrated, vomiting repeatedly, or your intake has become extremely poor.

Author and review information

Prepared for: aspergillosis.org

Purpose: general educational information for patients and non-specialists

Review note: Because medicine instructions can change between formulations and brands, patients should always check the current advice supplied with their own prescription and confirm uncertainties with a pharmacist or clinical team.

References and further reading

  1. Carter C, Muldoon EG, Kosmidis C. Chronic pulmonary aspergillosis - a guide for the general physician. 2024.
    PubMed
  2. Tashiro M, Takazono T, Izumikawa K. Chronic pulmonary aspergillosis: comprehensive insights into epidemiology, diagnosis, treatment, and unresolved challenges. 2024.
    Free full text
  3. Roboubi A, et al. Allergic bronchopulmonary aspergillosis. 2023.
    PubMed
  4. Sunman B, et al. Current approach in the diagnosis and management of allergic bronchopulmonary aspergillosis in children with cystic fibrosis. 2020.
    Free full text
  5. Madhavan V, et al. Malnutrition in allergic bronchopulmonary aspergillosis complicating asthma. 2023.
    Free full text
  6. British Dietetic Association. Spotting and treating malnutrition.
    BDA resource
  7. BAPEN. Food first / food enrichment.
    BAPEN resource
  8. BAPEN / Malnutrition Pathway. Managing malnutrition in COPD.
    PDF
  9. NICE. Managing malnutrition in COPD, The Malnutrition Pathway.
    NICE shared learning resource
  10. NHS. Heartburn and acid reflux.
    NHS advice
  11. Cambridge University Hospitals NHS Foundation Trust. Dietary and lifestyle advice for adults with gastro-oesophageal reflux disease (GORD).
    CUH advice
  12. NICE BNF. Itraconazole.
    BNF drug monograph
  13. Manchester University NHS Foundation Trust, National Aspergillosis Centre. Patient Information: Itraconazole.
    PDF
  14. Manchester University NHS Foundation Trust, National Aspergillosis Centre. Patient Information: Voriconazole.
    PDF
  15. Oxford University Hospitals NHS Foundation Trust. Advice about antifungals.
    PDF
  16. Balfour-Lynn IM. Milk, mucus and myths. Archives of Disease in Childhood. 2019.
    Article
  17. Pinnock CB, Graham NM, Mylvaganam A. Relationship between milk intake and mucus production in adult volunteers challenged with rhinovirus-2. 1990.
    PubMed
  18. ASCIA. Milk, mucus and cough.
    Patient resource

Diet and Aspergillosis: What Helps, What Doesn’t, and What Matters Most

Last reviewed: 8 April 2026

Many people living with aspergillosis ask whether diet can help “fight” the fungus, reduce symptoms, or improve recovery. This is completely understandable, particularly given the large amount of advice online suggesting that certain foods, supplements, or diets can control fungal disease.

This article explains what current evidence shows, what diet can and cannot do, and where it genuinely matters for people living with aspergillosis.

Core principle: Aspergillus-related disease is driven by what we breathe in and how the body responds — not by what we eat.


Contents


Key points

  • There is no diet that treats aspergillosis.
  • Aspergillus-related disease develops through inhalation of spores, changes in the lungs, and immune responses.
  • Diet does not control Aspergillus growth in the lungs.
  • Diet still matters for strength, weight, recovery, and treatment safety.
  • Food can affect how medicines are absorbed and metabolised.
  • Many popular online diet claims are based on misunderstood science, oversimplification, or marketing.

Back to top ↑


What do we mean by “no evidence”?

When this article says there is “no evidence” or “no strong evidence”, this does not mean that we are simply waiting for proof to arrive.

In most cases, it means one of two things:

  • the idea has been studied and has not been shown to help real patients, or
  • there is only laboratory or theoretical evidence, which does not translate into benefit in real-world disease

For example, fungi can grow in sugar-rich laboratory conditions. That does not mean eating sugar feeds Aspergillus in the lungs. The body tightly regulates blood glucose, and lung disease is far more complex than a laboratory culture dish.

Key message: when clinicians say there is “no evidence”, they usually mean an approach is unlikely to work in practice, not that it is a promising treatment that just has not been tested yet.

Back to top ↑


How Aspergillus disease develops

Aspergillus is a common environmental mould. People are exposed by breathing in microscopic spores from the air. Most people clear these spores without any problem.

Whether disease develops depends on the interaction between:

  • the condition of the lungs
  • how well mucus is cleared
  • the immune response

In healthy lungs, inhaled spores are trapped in mucus, moved out of the airways, and removed by immune cells. When this system is disrupted, Aspergillus may persist or trigger inflammation. This is described in clinical reviews of pulmonary aspergillosis such as Kosmidis & Denning, 2015.

This process takes place in the respiratory system and is driven by inhalation — not diet.

Back to top ↑


The role of airways, mucus and lung structure

The lungs have several important defence systems. These include mucus, cilia (tiny hair-like structures that move mucus), and immune cells. Together, they help remove inhaled particles and organisms.

In conditions such as asthma, bronchiectasis, chronic obstructive pulmonary disease (COPD), or other chronic lung diseases:

  • mucus may become thicker or harder to clear
  • airways may be damaged or widened
  • normal clearance may be less effective

This can make it easier for Aspergillus to remain in the lungs. In some people this contributes to allergic disease. In others, especially where there is structural damage, it can contribute to chronic infection.

These airway and lung-structure problems are not altered by avoiding particular foods.

Back to top ↑


Immune response and inflammation

In many people, particularly those with allergic forms of Aspergillus disease, symptoms are driven more by the immune system than by direct tissue invasion from the fungus.

For example, in allergic bronchopulmonary aspergillosis (ABPA), the body mounts an exaggerated allergic response to Aspergillus. This typically involves:

  • raised IgE antibodies
  • eosinophilic inflammation
  • airway swelling and mucus production

Reviews of ABPA describe these immune processes in more detail, including the overlap with asthma and cystic fibrosis-related airway disease, for example Knutsen & Slavin, ABPA review.

These immune pathways are complex and are not controlled by specific foods.

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Can food treat Aspergillus?

No specific food has been shown to treat Aspergillus-related lung disease.

You may come across claims about garlic, turmeric, coconut oil, probiotics, herbs, or “anti-fungal” foods. Some of these have shown antifungal effects in laboratory settings, but there is no reliable clinical evidence that eating them improves aspergillosis outcomes.

This is because:

  • food is processed in the digestive system, not the lungs
  • active compounds may not reach the lungs in useful amounts
  • the biology of lung disease is much more complex than simple fungal growth in a dish

Diet can support the body, but it is not a treatment for Aspergillus disease.

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Diet and ABPA (allergic disease)

In ABPA, the main problem is an allergic or immune reaction to Aspergillus. Diet does not switch that reaction on or off.

That means:

  • food does not “feed” ABPA
  • there is no evidence that an “anti-fungal diet” controls ABPA
  • restrictive diets do not treat the underlying immune process

However, diet can become more important because many patients with ABPA are treated with prednisolone or other corticosteroids. These medicines can affect appetite, weight, blood sugar, and bone health. NHS information on prednisolone describes common effects such as weight gain, increased appetite, and longer-term bone risks: NHS Prednisolone guidance.

So in ABPA, diet often matters more in relation to treatment effects than in relation to the fungal trigger itself.

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Allergy vs infection: why diet is often misunderstood

Many patients understandably ask whether a certain food might be “triggering” symptoms. This can be confusing because aspergillosis includes both allergic and infectious forms.

What matters here is the route of exposure:

  • Aspergillus-related lung disease is driven by inhaled spores
  • food enters the body through the digestive tract

Symptoms that seem to occur after eating may actually relate to:

  • acid reflux
  • throat irritation
  • airway sensitivity
  • coincidental fluctuation in symptoms

These may be real and troublesome, but they are not the same thing as diet directly driving Aspergillus disease.

Key message: Aspergillus-related lung symptoms are driven by what you breathe in and how your immune system responds — not by what you eat.

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Diet and CPA (chronic infection)

Chronic pulmonary aspergillosis (CPA) is different from ABPA. CPA tends to occur in lungs that are already damaged or structurally abnormal, for example after tuberculosis, with bronchiectasis, or with COPD.

In CPA, the key issue is not food intake but the presence of abnormal lung tissue where Aspergillus can persist. This broader clinical picture is outlined in reviews such as Kosmidis & Denning, 2015.

Diet does not alter fungal growth directly, but it can matter because some people with CPA experience:

  • weight loss
  • fatigue
  • low appetite
  • reduced physical strength

In CPA, diet is therefore mainly about maintaining strength, resilience, and recovery — not about “starving” the fungus.

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Why nutrition still matters

Although diet does not treat Aspergillus directly, nutrition still matters a great deal. Good nutrition supports the whole body, including the respiratory system.

Good nutrition can help support:

  • muscle strength, including the muscles used for breathing
  • energy levels
  • general immune function
  • recovery from illness and treatment

Poor nutrition, by contrast, can contribute to:

  • tiredness
  • lower resilience
  • reduced strength
  • slower recovery

This is one reason why very restrictive diets can be unhelpful, especially for patients already coping with chronic disease, breathlessness, or weight loss.

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Steroids and diet

For patients taking corticosteroids such as prednisolone, diet becomes particularly relevant.

Important issues can include:

  • increased appetite
  • weight gain
  • raised blood sugar
  • fluid retention
  • longer-term bone health

From a practical point of view, this is one of the strongest reasons to think carefully about diet in aspergillosis care. Here, diet is not being used to treat the fungus; it is helping patients cope with the effects of treatment and maintain overall health.

For longer-term steroid use, adequate calcium intake and attention to bone health may also be important. This is particularly relevant for people already at risk of osteoporosis.

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Diet and antifungal medication

The clearest and most important direct link between diet and aspergillosis care is through medication.

Food can affect how medicines are absorbed, broken down, or cleared from the body.

Food–drug interactions

Some foods and drinks affect enzymes in the liver that metabolise drugs. A well-known example is grapefruit, which can interfere with CYP3A4 and change drug levels in the body.

Taking antifungals correctly

Some antifungal medicines are affected by food. For example, voriconazole is usually taken on an empty stomach so that absorption is more reliable. This is described in professional guidance such as the British National Formulary (BNF).

Supplements and herbal products

Supplements are often marketed as “natural”, but they can still interact with prescription medicines. Some herbal products may alter drug metabolism and therefore affect antifungal treatment.

Key message: diet rarely affects Aspergillus directly, but it can be very important in how your medicines work.

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Checking food–drug interactions

Reliable sources for checking medicine and food interactions include:

It is also important to understand the limits of specialist tools. Drug-interaction tools designed specifically for antifungals are very useful for drug–drug interactions, but they do not usually include food interactions in a comprehensive way.

The safest source of advice remains your pharmacist or clinical team.

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Common diet myths (and why they persist)

Many people with aspergillosis come across strong claims online about diet and fungal disease. These often sound convincing, especially when symptoms are difficult to control and people understandably want something practical they can do.

However, most of these claims are based on misunderstandings of biology, laboratory research taken out of context, or commercial promotion.

Below are some of the most common myths, along with what current evidence suggests.

“Sugar feeds fungus”

This is one of the most common claims.

It comes from the fact that fungi can grow in sugar-rich laboratory conditions. However, this does not reflect what happens in the human body.

  • blood sugar is tightly regulated
  • Aspergillus in the lungs is not directly exposed to dietary sugar in the way people often imagine
  • there are no clinical studies showing that reducing dietary sugar improves aspergillosis outcomes

Why it persists: it sounds intuitive, it is easy to repeat, and it fits with heavily marketed “anti-fungal” diet programmes.

“Milk and dairy increase mucus”

This is a very common concern in respiratory disease generally.

Research does not show that dairy increases mucus production in the lungs. Some people notice a thicker or coated feeling in the mouth and throat after milk, but that is different from producing more mucus in the airways.

  • no good evidence of increased lung mucus
  • no evidence that dairy worsens Aspergillus disease itself

Why it persists: the mouth and throat sensation after dairy can easily be mistaken for a lung effect.

“Yeast in food causes fungal infection”

Foods such as bread or fermented products may contain yeast, but yeast used in food is not the same thing as Aspergillus.

  • food yeast and Aspergillus are different organisms
  • Aspergillus-related lung disease is linked to inhalation of environmental spores, not eating yeast-containing foods

Why it persists: the word “fungus” is used broadly, which can blur important differences between very different organisms.

“Avoid foods made with mould”

Some patients are advised online to avoid blue cheese, mushrooms, or other foods associated with moulds.

There is no good evidence that eating these foods changes Aspergillosis in the lungs.

  • the digestive and respiratory systems are separate
  • food moulds are not the same thing as inhaled environmental Aspergillus exposure

Why it persists: when a disease involves mould, it feels logical to avoid all mould-associated foods, even though the biology does not support that approach.

“Low-carb or ketogenic diets can starve the fungus”

This idea grows out of the “sugar feeds fungus” claim.

However:

  • the body keeps glucose within a narrow range
  • lung infections are not directly altered by short-term dietary carbohydrate restriction
  • there is no clinical evidence that low-carb or ketogenic diets improve aspergillosis outcomes

Why it persists: it sounds more scientific than it is, and it is frequently promoted in wellness and biohacking communities.

“Anti-fungal foods such as garlic, turmeric or coconut oil can treat aspergillosis”

Some of these substances show antifungal activity in laboratory experiments.

That is not the same as treating disease in people. The concentrations used in experiments are often very different from what is achievable through normal eating, and human lung disease is far more complex than a petri dish.

Why it persists: laboratory findings are often presented online as though they were proven clinical treatments.

“Detox diets or cleanses remove fungal infection”

There is no biological mechanism by which detox diets or juice cleanses remove Aspergillus from the lungs.

  • the lungs are not “cleansed” through the digestive tract
  • there is no clinical evidence supporting detox approaches in aspergillosis

Why it persists: detox language is emotionally appealing, especially when people feel unwell and want a sense of control.

“Candida overgrowth” diets apply to aspergillosis

Many patients come across “anti-Candida” diets and wonder whether the same advice applies to Aspergillus.

These diets often recommend:

  • cutting out sugar
  • avoiding carbohydrates
  • removing yeast-containing foods
  • following restrictive “anti-fungal” eating plans

However, these ideas are based on a different organism and a different part of the body.

Candida vs Aspergillus: important differences

  • Candida is a yeast commonly found on the skin and in the gut
  • Aspergillus is a mould in the environment that is inhaled into the lungs

Aspergillus-related disease such as ABPA or CPA affects the lungs and is driven by inhaled spores, not by changes in the gut.

Do “anti-Candida diets” affect Aspergillus?

There is no clinical evidence that diets designed to reduce Candida:

  • affect Aspergillus in the lungs
  • reduce allergic responses to Aspergillus
  • improve outcomes in aspergillosis

These diets often rely on the same assumptions as other myths, especially the idea that “sugar feeds fungus”. Those assumptions do not fit how Aspergillus lung disease works.

What about the gut microbiome?

There is real scientific interest in the gut microbiome and its role in health. However, there is currently no evidence that changing diet to target gut fungi alters aspergillosis outcomes.

This is an area of research interest, but it is not a basis for dietary treatment at present.

Why these diets can be unhelpful

Restrictive anti-Candida or “anti-fungal” diets can sometimes lead to:

  • reduced calorie intake
  • weight loss
  • nutritional imbalance
  • anxiety around food

This can be particularly unhelpful in people with chronic lung disease who need to maintain strength and energy.

Key message: diets designed for “Candida overgrowth” are not relevant to aspergillosis and are not supported by evidence in this context.

“If symptoms improve after changing diet, the diet must be working”

This is a very understandable conclusion, but it can be misleading.

Symptoms in aspergillosis often fluctuate because of:

  • natural variation in disease activity
  • environmental exposure
  • allergy activity
  • medication changes

An improvement may happen at the same time as a dietary change without being caused by that change.

Advice from non-mainstream or alternative sources

Many people with long-term or difficult-to-control conditions look beyond standard medical care for additional answers. This is entirely understandable, especially when symptoms are persistent or uncertain.

You may come across advice from practitioners or online sources who describe themselves as offering “functional”, “integrative”, or “alternative” approaches. These often include:

  • strict or highly restrictive diets
  • “anti-fungal” or “detox” protocols
  • long lists of supplements
  • tests or diagnoses that are not widely used in NHS practice

Some of this advice may sound detailed or scientific. However, it is important to understand that:

  • many of these approaches are not supported by clinical evidence in aspergillosis
  • they may be based on theories that do not reflect how lung disease develops
  • they are often not part of standard respiratory or infectious disease care

In some cases, following this advice can lead to:

  • unnecessary dietary restriction
  • weight loss or nutritional problems
  • delays in receiving appropriate medical treatment
  • confusion about symptoms and diagnosis

This does not mean that all non-mainstream approaches are harmful, but it does mean they should be approached with care.

Key message: if you are considering advice outside standard medical guidance, it is usually helpful to discuss it with your clinical team or pharmacist so it can be considered safely alongside your current treatment.

Overall message: many diet claims are based on ideas that sound plausible but do not reflect how aspergillosis works in the body.

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A practical, evidence-based approach

For most people with aspergillosis, the most sensible and evidence-based approach is:

  • eat a balanced diet
  • maintain weight and strength
  • include regular sources of protein
  • avoid unnecessarily restrictive diets
  • follow medicine-specific instructions carefully
  • check food–drug interactions rather than relying on social media advice

Focus on supporting your body and treatment — not trying to treat Aspergillus through diet.

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When to seek help

It may be worth asking for extra support if you are experiencing:

  • unintentional weight loss
  • poor appetite
  • difficulty managing steroid-related appetite or weight changes
  • concerns about blood sugar or bone health
  • questions about food–drug interactions

Pharmacists, GPs, specialist teams, and where appropriate dietitians can all help with these issues.


References

This article is for general information and should not replace advice from your own clinical team.