Ramadan Fasting Doesn't Worsen Asthma in 120 Patients: What the Research Shows

Medical disclaimer: This article summarises published research for informational purposes only. It is not medical advice and is not a substitute for guidance from a qualified health professional. Always consult your doctor before starting any fasting protocol, especially if you have an existing health condition or take medication.

Study at a Glance

What This Study Looked At

Many people with asthma worry that going a full day without food or water during Ramadan could make their symptoms worse. Researchers in Iran set out to test this directly: does daytime fasting during Ramadan change lung function or asthma control in people who already have moderate to severe asthma? This matters well beyond religious fasting — it speaks to a broader question people ask about whether intermittent fasting is dangerous for people with existing health conditions, and whether extended periods without food or water are safe for people managing a chronic respiratory condition.

Who Was Studied

Participant profile: All 120 participants had a clinical diagnosis of moderate to severe asthma. Spirometry (a lung function test measuring FEV1, FVC, PEF, and the FEV1/FVC ratio) was performed before Ramadan began and again after it ended, alongside a standard asthma control assessment.

How the fasting protocol worked: Ramadan fasting involves abstaining from all food and drink, including water, from before sunrise until sunset each day for approximately one month — a stricter daily protocol than most Western time-restricted eating approaches, which typically still allow water and non-caloric beverages.

What the Researchers Found

Lung Function (Spirometry)

The core comparison was whether FEV1, FVC, PEF, and the FEV1/FVC ratio changed differently in the fasting group compared to the non-fasting group between the start and end of Ramadan.

• Spirometric measurements were not significantly different before and after Ramadan within either group.
• There was no significant difference between the fasting and non-fasting groups in how these measurements changed over the month.
• Notably, FEV1 showed a larger positive change from baseline in the fasting group compared to the non-fasting group — a trend the authors flagged as a potential positive signal, while cautioning it did not reach statistical significance in this sample size.

Asthma Severity and Control

• Overall asthma severity and control status were assessed alongside spirometry and did not show a meaningful worsening in the fasting group relative to the non-fasting group.

What Did Not Change

• No significant deterioration in FEV1, FVC, PEF, or FEV1/FVC ratio was observed in fasting patients compared to non-fasting patients.
• No significant increase in asthma severity was reported as a result of fasting.

What the Researchers Concluded

The authors concluded that fasting during Ramadan does not significantly worsen spirometric findings or asthma severity in patients with moderate to severe asthma, and that fasting can generally be considered safe for people with stable asthma. They noted that the modestly larger FEV1 improvement seen in the fasting group deserves follow-up in a properly randomized trial.

What This Means If You Fast

• Stable asthma and fasting can coexist. This study found no evidence that a full month of daily dawn-to-sunset fasting worsened lung function or asthma control in people with moderate to severe asthma.
• This is not a green light without medical input. People with asthma should still confirm with their doctor that their condition is stable and well-controlled before attempting any extended fast, especially one that also restricts water.
• Western intermittent fasting is a gentler comparison. Typical 16:8 or OMAD protocols allow water, herbal tea, and black coffee throughout the fast — a meaningfully less restrictive approach than the water-free Ramadan protocol studied here.
• Watch your own symptoms, not just the averages. Group-level results don't guarantee an individual response; anyone noticing increased wheezing, breathlessness, or rescue-inhaler use while fasting should stop and speak with their doctor.
• The FEV1 trend is interesting but not proof of benefit. A larger improvement in one lung function measure in the fasting group is worth further study, not a reason to expect fasting to actively improve asthma.
• Related reading: does fasting improve brain function and focus covers another area where fasting's effects are still being actively researched.

Study Limitations

• Full numerical tables were not directly retrievable at the time of writing due to database access restrictions, so exact p-values and mean spirometry figures could not be independently verified beyond the published abstract and conclusion.
• This is an observational cohort study, not a randomized controlled trial — fasting status was based on the patients' own choice or medical exemption, which can introduce selection bias (healthier patients may have been more likely to choose to fast).
• The study population was limited to patients with moderate to severe asthma in one geographic region (Iran), which may limit how well the findings generalize elsewhere.
• Ramadan fasting is a specific, water-restricted protocol; findings may not directly translate to Western-style intermittent fasting, which permits water and non-caloric drinks.
• Funding source was not reported in available sources.

Source

Ghaffary MR, Talei A, Moradian M, Ghaffari S. (2022). The effect of fasting on spirometry indices and respiratory symptoms in asthmatic patients. Journal of Cardiovascular and Thoracic Research, 14(2), 116–121. PMID: 35935392

Frequently Asked Questions

Does fasting make asthma worse?

This study of 120 patients found no significant worsening of lung function (FEV1, FVC, PEF) or asthma severity in patients who fasted throughout Ramadan compared to those who didn't.

Is it safe for asthma patients to fast?

The researchers concluded that fasting can generally be considered safe for patients with stable, moderate to severe asthma, though they recommend individualized medical guidance rather than a blanket rule.

Did fasting actually improve lung function in this study?

FEV1 showed a somewhat larger improvement from baseline in the fasting group than the non-fasting group, but this difference did not reach statistical significance, so it's best read as a signal for future research rather than a proven benefit.

Is Ramadan fasting the same as intermittent fasting?

Not exactly — Ramadan fasting restricts both food and water from dawn to sunset, while most intermittent fasting protocols (like 16:8) allow water, herbal tea, and black coffee throughout the fast.

Should someone with asthma try intermittent fasting?

Based on this study, stable asthma doesn't appear to be an automatic barrier to fasting, but anyone with asthma should discuss it with their doctor first, particularly around medication timing and symptom monitoring.

Related Research and Articles

• Does intermittent fasting reduce inflammation?
• Does fasting improve brain function and focus?
• What is extended fasting and is it safe?
• Can intermittent fasting improve gut health?
• Is intermittent fasting dangerous?
• Can diabetics do intermittent fasting?

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