Did you know that there are approximately 150 million Muslims with diabetes worldwide, most of them will be fasting and will need help?

This article will provide all the information you need to manage diabetes whilst fasting. If you have diabetes, save this article for future reference or pass this on to colleagues and friends who have diabetes. These are desperate times and we are in the middle of a pandemic. I will also be discussing fasting whilst isolating and maintaining social distance during Ramadan. I will also include the advice provided by an Imam.

Ramadan is the Islamic holy month where fasting is compulsory for all healthy Muslims. Absolute fast between sunrise and sunset is recommended and people who are fasting should refrain from:

  • Food
  • Liquids
  • Medication

There are no restrictions on medications, food or fluid intake between sunset and sunrise. People fasting during this month can have two meals per day:

  • Sehri (before dawn)
  • Iftar (after sunset)

Fasting is not easy, especially if this has to be followed along with prayers and for the whole month of Ramadan. It is more difficult if you’re in between a pandemic and asked to isolate. Fortunately, this year, the duration of the fast is around 16 hours in the United Kingdom. Traditionally during the holy month of Ramadan, Muslims around the world engage in communal prayers, spiritual reflection and meals with family and friends after breaking their fast. This year staying at home throughout the holy month will be challenging, it is necessary to follow the advice of your government, to save lives and protect yourself. Isolating and fasting with diabetes is more difficult but can be done successfully, if you follow certain rules.

I am always fascinated by people working in submarines and astronauts, who spend a lot of time in isolation. How are they keeping themselves mentally and physically healthy?

Six key factors for success whilst isolating include:

  • Planning and having a clear routine.
  • Split your day into blocks of 2-3 hours.
  • Strictly allot time for cleaning, eating, sleeping and prayers.
  • Avoid watching news all the time.
  • Communicate with family and Friends.
  • Go out for a walk and exercise regularly.

Ramadan is not mandatory for the following groups:

  • Children
  • Elderly
  • Acute medical illness (e.g. Infections, fever, nausea or vomiting, unexplained weight loss etc.)
  • Pregnant or nursing mothers
  • Menstruating women
  • People with chronic illness (e.g. diabetes, chronic kidney disease, cardiovascular disease)

Patients with diabetes are exempted from fasting during Ramadan, if they are at high risk of complications. However, many Muslims with diabetes insist on fasting during Ramadan and their wishes should be respected, if it is safe to do so.

Muslims with Diabetes who should NOT fast include:

  1. Unawareness (no warnings) to hypoglycaemia (low blood sugar)
  2. Type 1 diabetes with recurrent ketoacidosis
  3. Gestational diabetes
  4. Pregnancy or lactating
  5. Menstruating
  6. Infections
  7. Children
  8. Poor vision, kidney failure, heart failure or any other illness complicating diabetes
  9. Elderly

People with diabetes with any of the above conditions, who wish to fast, should consult their diabetes doctor/nurse and their local Imam.

What are the common problems encountered during Fasting for people with diabetes?

Based on the EPIDIAR and CREED study, most common problems include: 

  • High blood glucose or hyperglycaemia
  • Low blood glucose or hypoglycaemia
  • Dehydration
  • Diabetic ketoacidosis (DKA)
  • Thrombosis

So, what are symptoms of hyperglycaemia or high blood glucose?

Early feature of hyperglycaemia include:

  • Tiredness
  • Excessive or Increased thirst
  • Dull headache
  • Difficulty in concentrating
  • Blurring of vision
  • Increased frequency of urination
  • Weight loss

Indirect or long-term features of hyperglycaemia include:

  • Damage to eyes
  • Kidney damage
  • Delayed wound healing
  • Erectile dysfunction
  • Vaginal infections like thrush
  • Nerve damage
  • Altered bowels

What are symptoms of hypoglycaemia or low blood glucose?

People can have one or more symptoms. There is no particular sequence for these symptoms. Early signs of a hypoglycaemia or low blood sugar include:

  • Hunger
  • Tiredness
  • Irritable and moody
  • Sweating
  • Tingling of lips
  • Shaky or trembling
  • Dizziness
  • Palpitations

If low blood glucose is not corrected, you may develop other symptoms, which include:

  • Difficulty concentrating
  • Blurred vision
  • Confusion
  • Abnormal behaviour
  • Slurred speech
  • Feeling sleepy
  • Seizures
  • Collapse and loss of consciousness

What are the likely symptoms of Dehydration? 

  • Dry mouth
  • Muscle cramps
  • Nausea
  • Vomiting
  • Palpitations

Diabetes Ketoacidosis (DKA)

DKA is more common in people with type 1 diabetes. This happens when they have not had adequate insulin. This is a life-threatening condition and should seek immediate help from an emergency department. Due to lack of insulin, the body produces lots of ketones and acids. This results in dehydration, confusion and can lead to serious consequences.


In people with diabetes, due to high blood glucose and dehydration, there is a tendency to form clots in the lungs and elsewhere in the body, which again is a life-threatening condition. If you have unexplained pain or swelling in your calf or short of breath you should seek help immediately.

How should people with diabetes plan for Ramadan?

So, once you have decided on fasting, you should plan well ahead for Ramadan. Fasting during Ramadan not only uplifts you spiritually and physically but also helps you to significantly improve your blood glucose control and to lose weight if you are overweight or obese.

When I see patients in my diabetes clinic, I advise them on how to improve their blood glucose control and adapt to a healthy lifestyle. The usual excuse from people, whose blood glucose control is not good is that they are too busy and do not have time. In that case, now is the time to focus on your health, help yourself, your family and your country. Look after yourself.

Please consult your diabetes specialist team to undergo pre-Ramadan assessment and receive a structured education related to physical activity, meal planning, glucose monitoring and dosage/ timing of medications.

Please note, you should have a personalised plan and do not adopt a plan provided to someone else. People with diabetes have different needs and the plan has to be individualised.

Please ensure you have an appointment with your doctor or diabetes nurse before Ramadan. Ensure you have a clear idea on how to manage low and high blood glucose and also how medications should be altered whilst fasting. Please also see a dietitian and agree on a meal plan and activity schedule. Get your blood tests and blood pressure checked following this consultation.

In view of COVID-19 pandemic and isolation recommended, please ensure you have adequate stock of medications. Ketone measuring equipment, Blood glucose meter and strips. You should also have a contact number of your diabetes team or your doctor, in case you need any assistance. If, however you are confused and are not able to contact a healthcare team, you should stop fasting and take your usual medications and ensure you are well hydrated.

Physiology of fasting

What happens to your body during fasting? What changes take place inside your body?

You eat, to provide energy to the different organs in the body, thereby sustaining life. When you do not eat, your body craves for energy and you feel hungry. When you continue to fast, your body starts using up the stores. Glucose in the liver is stored as glycogen. So, when you do not eat for a long duration, glycogen in the liver is converted to glucose.

After a day or two of fasting when all the glycogen in the liver is used up, you start to break down fat. Fat in the body is broken down to fatty acids, which is used up by the organs in the body. When too much fat is broken down, ketones are produced which again is a source of energy. Ketones blunt the appetite centre in the brain. This is why you do not feel so hungry after the first few days. During fasting for Ramadan, the first few days are difficult as your body tries to accommodate for the reduced energy provided by food.

The above mentioned process is adapted by the so-called ketogenic diets. That is by reducing the carbohydrate intake of food, your body breaks down the fat and produces ketones and suppresses your appetite. By the way, ketogenic diets do not work well in the long run as far as losing weight is concerned. Once you stop the ketogenic diet, usually there is rebound weight gain. Unless you have gradually shifted to a healthier diet and lifestyle.

Management of diabetes during the month of Ramadan

 Management of diabetes during the month of Ramadan will depend on:

  1. Type of diabetes
  2. Medications
  3. Blood glucose control

The most important aspect in diabetes management during Ramadan is to prevent hypoglycaemia or low blood glucose, that is below 4mmol/l or 72mg/dl.  In order to prevent hypoglycaemia, management plans must be individualised to your needs. Ideally this new plan should be practiced for at least a month or two before Ramadan. If you do have hypoglycaemic episodes requiring correction with food, liquids or medications, you can always compensate by fasting at a later date or feed the hungry and poor (Fidyah).

People with diabetes may be treated with

  • Diet alone
  • Sulphonylureas (glyburide, glimepiride, gliclazide, glibenclamide)
  • Metformin
  • Pioglitazone (Actos)
  • Gliptins (Saxagliptin, Sitagliptin, Linagliptin,Vildagliptin)
  • GLP-1 analogues (Victoza, Bydureon, Lyxumia, Trulicity)
  • SGLT-2 inhibitors (Forxiga, Invokana and Jardiance)
  • Insulin

A significant number of people will be treated with a combination of these medications.

DO NOT make any changes to your treatment, until you have consulted your doctor.

General advice for people with diabetes fasting during Ramadan:

  • For Sehri, that is before starting the fast, include low Glycaemic Index (Low GI) or more slowly absorbed food like basmati rice, dhal (pulses) and non-root vegetables in your meal.
  • Check your blood glucose levels more often than you would normally do.
  • For Iftar, that is when you break the fast, have a small portion of food, and avoid eating only sweets, fried or salty food.
  • Do not skip meals before the break of dawn, that is when you commence the next day’s fast
  • Ensure you keep yourself well hydrated after the end of fast. You can have water, sugar-free drinks and decaffeinated beverages.
  • If you are on blood pressure lowering tablets. You will need to monitor your blood pressure and if you are feeling dizzy you should consult your doctor to adjust the dose of medications.

Medication recommendation for during fasting for Ramadan


It is generally recommended that those who have diet-controlled diabetes and those who are on Metformin, Acarbose, Pioglitazone (Actos), Gliptins need not make any changes to the dose. However, some people may need reduction in dose and skip the mid-day dose of Metformin. That is if you are on Metformin three times a day, reduce the dose to twice a day.

SULPHONYLUREAS (Glyburide, Glimepiride, Gliclazide, Glibenclamide)

Dosage adjustment is needed for people taking sulphonylureas and insulin. Some people need to either reduce dose or stop sulphonylureas in the morning.

If you are on a single daily dose (eg Glipizide, Glimepiride), you should take that with the sunset meal at a reduced dose. Some people can switch to a short acting medication like gliclazide to prevent low blood glucose.

GLP-1 analogues (Bydureon, Trulicity, Victoza, Lyxumia)

No change in dose is required for this group of drugs during Ramadan. However, it is preferable to take the injection after Iftar. Please ensure you are well hydrated whilst on Victoza, Bydureon, Trulicity or Lyxumia.

However, if you are on a combination of medications, please make sure those medications are adjusted accordingly.

SGLT2i (Canagliflozin, Dapagliflozin, Empagliflozin)

This medication is safe to take during Ramadan. However, elderly people need to be careful and also people living in countries where it is hot, have to ensure that they remain well hydrated.


After consulting with your doctor or diabetes nurse, if you have decided to fast, ensure you monitor your blood glucose more frequently. You will require less insulin before the start of the fast.

Low blood glucose is more frequent in patients on insulin, specifically basal bolus regime (combination of long acting and multiple short acting insulins) or premixed insulins (Humulin M3, Humalog Mix25) and adjustment of insulin doses is recommended.

Change or reduction in dose of insulin depends on the type of insulin, blood glucose levels and duration of fasting. Generally, people take one third of their daily dose in the morning and two thirds of the evening dose after breaking their fast, especially if you are on a mixed insulin like Humulin M3, Humalog Mix25 etc. However, this varies greatly and hence dose change varies from person to person.

If you happen to be on a long acting insulin and short acting insulin. The lunch time short acting insulin is not taken. The long acting insulin is taken late evening. The dose needs to be adjusted based on your blood glucose. Sometimes you may have to change the type of long acting insulin to prevent low blood glucose.

What advice does an Imam have for people with diabetes?

Respected Mufti Zakaria Akudi, from the UK says that people with diabetes can fast provided they do not have any complications and they can alter their medications based on medical advice. However, it is not always easy to fast, especially for people with diabetes when the days are long and/or they have serious underlying medical conditions. Scholars of Islam provide two options for people who cannot fast during the month of Ramadan, these are:

  1. Move fasting to winter months when days are shorter and if they can cope with fasting in winter months.
  2. People who cannot fast even during winter days, guidance in Islam is to offer approximately a pound a day to the poor and needy. This is the allowance Islam has provided and hence, people should not harm themselves by fasting, if they have a serious medical condition.

Summary: How to remain Safe during Fasting?

  • Always have a plan for food, activity, sleep and hydration.
  • Always carry sugary drinks, diabetes identification medical bracelets and glucose monitoring devices with you.
  • If you are likely to have hypoglycaemia, check your blood glucose frequently.
  • People with Type 1 diabetes should NOT stop insulin and ALWAYS consult a doctor before making any changes.
  • If your blood glucose is less than 4.0mmol/l or 72gm/dL, end your fast immediately and treat the low blood sugar level.
  • If your blood glucose level is below 4.0mmol/l or 72gm/dl at the start of the fast and you are on insulin or sulphonylureas (or any other medication that can cause a hypoglycaemia), do not fast and treat your hypoglycaemia immediately
  • If your blood glucose level is higher than 16.7mmol/l or 300mg/dL, end the fast immediately and correct high blood glucose.
  • If you become dehydrated, end the fast immediately and have a drink of water.
  • If you start to feel unwell, disoriented, confused, if you collapse or faint, stop fasting and have a drink of water or other fluid.


Those of you who prefer to watch a video on the same topic, please click here: https://www.youtube.com/watch?v=mgS1tFMUl7o


Dr. C. Rajeswaran FRCP(UK);MSc  Consultant Physician(Diabetes, obesity & Endocrinology)

Director, simplyweight


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