Printed on: February 23rd, 2025
Ramadan: impact on diabetes and other chronic diseases
Ramadan: impact on diabetes and other chronic diseases
During Ramadan, many of our Muslim patients will want to fast, fasting being one of the five pillars of the Muslim faith. How best can we support them in this?
The fast of Ramadan lasts from dawn to sunset for a period of 29 or 30 days. Following the lunar calendar, the fasting month is brought forward by about 10 days each year, and currently falls during the UK spring months.
In 2025, Ramadan will start on 1 March and end on 30 March. During this time, people will generally eat two meals a day: one before sunrise (Suhoor) and one after sunset (Iftar). No fluids or food are taken during daylight hours. This includes water and, often, medicines too.
This article was updated in February 2025.
Impact of fasting
A BMJ Practice Pointer acknowledged that fasting may impact chronic disease control (BMJ 2022;376e:063613). The authors recommended a structured pre-Ramadan review for people with:
- Diabetes .
- Adrenal insufficiency.
- Thyroid disease.
- Cancer.
- Epilepsy.
- Severe enduring mental illness.
- Eating disorders.
- Those who are pregnant or breastfeeding.
- Occupational factors, e.g. shift workers and those operating heavy machinery.
Many Muslims, even those who could seek exemption, want to participate in fasting in Ramadan. We will want to respect that decision and work with people to achieve the best outcomes.
- Start planning for Ramadan at least 6–8w before: pre-Ramadan education reduces the risk of harm.
- Dietary advice that applies to the rest of the year should be followed in Ramadan, but the meals, particularly Iftar (the evening meal), are often celebratory in nature and involve higher calorie and sugar intake than normal. Suhoor (the morning meal) is often relatively small, so, for some, drug dose adjustments are needed to get people through the day without problems.
- Pay special attention to medications that can cause dehydration (diuretics) or hypoglycaemia (insulin/sulphonylurea), or that may be affected by change in routine (antiepileptics/thyroid medication).
- Seek specialist input for patients where there is any uncertainty about how to safely manage fasting.
Consider a brief ‘trial’ fast in the months before Ramadan to monitor the effect on disease management. For example, this might be an opportunity to monitor blood glucose and adjust insulin dosing.
For those who cannot fast safely, there are other options permitted by religious leaders:
- A delay in fasting to allow a period of acute illness or pregnancy/breastfeeding to pass.
- Charity (fidyah) for those unable to make up their fasts.
The remainder of this article relates to diabetes (type 1 and 2) in Ramadan.
Diabetes management in Ramadan
In 2021, the International Diabetes Federation (IDF) (funded by an unrestricted educational grant by Sanofi) updated its helpful guide on diabetes during Ramadan. Here are the key points.
The main risks during Ramadan are of hypo- and hyperglycaemia, diabetic ketoacidosis and dehydration (which can lead to thrombosis).
Stratify patients into one of three categories – high, moderate and low risk – using the IDF-DAR risk calculator. Management is based on risk. As you look at the scoring system below, bear in mind that:
- Those scoring ≤3 are considered low risk.
- Those scoring 3.5–6 are moderate risk.
- Those scoring >6 are high risk.
| Risk factor | Score | |
| Diabetes type | ||
| – | Type 1 | 1 |
| Type 2 | 0 | |
| Diabetes duration | ||
| – | <10y | 0 |
| ≥10y | 1 | |
| Hypoglycaemia | ||
| – | Hypoglycaemia unaware | 6.5 |
| Recent severe hypoglycaemia | 5.5 | |
| Multiple weekly hypoglycaemic events | 3.5 | |
| Hypoglycaemia <once per week | 1 | |
| No hypoglycaemia | 0 | |
| Level of glycaemic control | ||
| – | HbA1c >75mmol/mol (9%) | 2 |
| HbA1c 58–74mmol/mol | 1 | |
| HbA1c <58mmol/mol (7.5%) | 0 | |
| Type of treatment | ||
| – | Multiple daily mixed insulin injections | 3 |
| Basal bolus/insulin pump | 2.5 | |
| Once-daily mixed insulin | 2 | |
| Basal insulin | 1.5 | |
| Glibenclamide | 1 | |
| Gliclazide/MR or glimepiride or repaglinide | 0.5 | |
| Other therapy not including SU or insulin | 0 | |
| Self-monitoring of blood glucose | ||
| – | Advised and not completed | 2 |
| Completed suboptimally | 1 | |
| Completed as indicated | 0 | |
| Acute complications (DKA/HONK) | ||
| – | In past 3 months | 3 |
| In past 6 months | 2 | |
| In past year | 1 | |
| No DKA/HONK | 0 | |
| Macrovascular complications | ||
| – | Unstable | 6.5 |
| Stable | 2 | |
| None | 0 | |
| Renal complications | ||
| – | eGFR <30ml/min | 6.5 |
| eGFR 30–45ml/min | 4 | |
| eGFR 45–60ml/min | 2 | |
| eGFR >60ml/min | 0 | |
| Pregnancy | ||
| – | Pregnant: poorly controlled | 6.5 |
| Pregnant: well controlled | 3.5 | |
| Not pregnant | 0 | |
| Frailty and cognitive function | ||
| – | Frail or cognitive impairment | 6.5 |
| 70 and no home support | 3.5 | |
| Not frail | 0 | |
| Physical labour | ||
| – | Intense | 4 |
| Moderate | 2 | |
| None | 0 | |
| Previous Ramadan experience | ||
| – | Overall negative | 1 |
| No negative experience | 0 | |
| Fast duration (hours) | ||
| – | ≥16 | 1 |
| <16 | 0 | |
On the basis of the score from the table above, the suggested management is as follows:
| Management during Ramadan | ||
| High risk (score >6) | Moderate risk (score 3.5–6) | Low risk (score 0–3) |
| Should not fast. | Should be advised not to fast. | Should be able to fast. |
| If they wish to fast, they should: |
Before fasting: |
|
Patient education
Pre-Ramadan education should take place a minimum of 6–8 weeks before Ramadan, and be repeated annually.
It should involve:
- A structured risk assessment.
-
Self-monitoring blood glucose training:
- Teach how for those who might not normally do this as part of their diabetes management.
- How to adjust medication depending on results (see below).
-
Dietary advice:
- Divide daily calories between Suhoor and Iftar, plus 1–2 snacks if necessary.
- Ensure meals are well balanced: 45–50% carbohydrate (ideally unrefined carbohydrates), 20–30% protein, <35% fat (preferably mono- and polyunsaturated).
- Include low glycaemic index, high-fibre foods that release energy slowly before and after fasting, e.g. granary bread, beans, rice.
- Include plenty of fruit, vegetables and salads.
- Minimise foods that are high in saturated fats, e.g. ghee, samosas, pakoras. Use small amounts of oil when cooking, e.g. olive, rapeseed.
- Avoid sugary desserts.
- Keep hydrated between sunset and sunrise by drinking water or other non-sweetened beverages. Avoid caffeinated and sweetened drinks.
- Exercise: avoid vigorous exercise (increased risk of hypos and dehydration), especially in the hours just before sunset.
-
Break the fast if:
- Blood sugar <3.9 or >16.6.
- Symptoms of hypo- or hyperglycaemia, or dehydration, develop.
- Symptoms of acute illness develop.
(In most countries, measuring blood sugar is not considered to be breaking the fast, but, in some areas, it is – ask!)
| Effects of fasting | ||
| Lifestyle changes when fasting | Physical and mental benefits | Potential adverse effects |
|
|
|
|
(International Diabetes Federation and DAR, Diabetes and Ramadan, Practical Guidelines 2021)
Adjusting medication
The following is a guide summarised from the International Diabetes Federation. Seek expert advice if you are uncertain, or there is significant hypo- or hyperglycaemia, or if the patient has other complications.
| Usually taken: | During Ramadan | |
| Metformin | Once daily | Take with Iftar (evening meal) |
| Twice daily | Take with Iftar and Suhoor (morning meal) | |
| Three times daily | Take morning dose with Suhoor Take lunchtime and evening doses together with Iftar |
|
| Slow-release metformin | Once daily | Take with Iftar |
| Sulphonylurea | Once daily | Take with Iftar |
| Twice daily | If well controlled, take lower-than-usual dose with Suhoor Take normal dose with Iftar |
|
| Gliptins | – | No dose adjustment needed |
| Pioglitazone | – | No dose adjustment needed – take with Iftar |
| Gliflozins (SGLT2 inhibitors) | – | Use with caution but no dose adjustment needed. Take with Iftar. Increase fluids in non-fasting hours if possible. |
| GLP-1s | – | No dose adjustment needed |
| On multiple medications | Variable | Those on more than 3 medications are at higher risk of hypoglycaemia. Doses of insulin and sulphonylurea should be reduced by 25–50%. |
Insulin in Ramadan
We strongly suggest you take advice on this unless you are confident about managing insulin doses in the context of the physiological changes that occur in fasting.
Dose adjustments depending on blood sugar
This is fractionally different from the dose adjustment above for pre-mixed insulin (the cut off is 7.2 not 7, for reasons that are not explained in the document).
| Fasting/pre-meal blood glucose | Adjust long-acting basal insulin by (this will be begin given with Iftar) or short-acting insulin by: |
| <3.9 or symptoms of hypoglycaemia | Reduce by 4 units |
| 3.9–5 | Reduce by 2 units |
| 5–7.2 | No change |
| 7.2–11.1 | Increase by 2 units |
| >11.1 | Increase by 4 units |
When to check blood sugar
In type 1 diabetes, patients should check pre-Suhoor (first meal of the day), mid-morning, noon, mid-afternoon, before the sunset meal of Iftar and before bed AND at any time when there are symptoms of hypoglycaemia.
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Ramadan: impact of diabetes and other chronic diseases |
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