Intended for healthcare professionals

Clinical Review

Management of people with diabetes wanting to fast during Ramadan

BMJ 2010; 340 doi: (Published 22 June 2010) Cite this as: BMJ 2010;340:c3053

Religious fasts after bariatric surgery

The requirement to observe a total fast (abstain from all forms of
nourishment including liquids) during daylight hours in the month of
Ramadan (reviewed by Hui and colleagues in the context of diabetes[1])
poses a greater challenge in the management of people who have undergone
bariatric surgery. Bariatric surgery is increasingly performed for the
correction of morbid obesity, particularly in people with co-morbid
conditions such as diabetes [2]. As most bariatric procedures limit the
amount of food or drink that can be consumed in one sitting, patients are
advised to sip fluids frequently through the day. A total fast during long
summer days would put these patients at risk of dehydration. Fasting for
long periods could lead to the desire to eat larger amounts at a faster
pace on breaking the fast. This could result in vomiting, compounding
dehydration and poor nutritional intake. Foods that are frequently eaten
at the sunset meal such as sweets and deep-fried pastries would also put
some patients at risk of dumping syndrome and/or steatorrhoea. The small
stomach volume may also pose a further difficulty with fitting in
nutritional supplements and medications around meal times.

Research in this area is virtually non-existent. Based on clinical
experience we recommend that:

• Patients should avoid total fasts in the first 12 – 18 months after
bariatric surgery when new eating and drinking habits are being

• Beyond this period the risk of post prandial vomiting is reduced
and patients who are otherwise in good health may observe religious fasts
if fluids can be taken through the day (e.g. fasting in the season of

• Patients should be advised to base their meals on complex
carbohydrates and high quality proteins to optimise their nutritional

• Patients who have had malabsorptive procedures such as gastric
bypass should be advised of the importance of continuing with their
nutrient supplements such as iron, calcium and vitamin D, and

Fiona Chan, specialist weight management dietitian

Chris Slater, specialist bariatric dietitian

Akheel A Syed, consultant physician

Department of Obesity Medicine, Salford Royal NHS Foundation Trust & University Teaching
Hospital, Salford, Greater Manchester M6 8HD


1. Hui E, Bravis V, Hassanein M, Hanif W, Malik R, Chowdhury TA, et
al. Management of people with diabetes wanting to fast during Ramadan. BMJ

2. Leff DR, Heath D. Surgery for obesity in adulthood. BMJ

Competing interests:
None declared

Competing interests: No competing interests

02 July 2010
Fiona Chan
Specialist weight management dietitian
Chris Slater, and Akheel A. Syed
Salford Royal NHS Foundation Trust & University Teaching Hospital