NHS Guide to Ramadan (Fasting)

Re: NHS Guide to Ramadan (Fasting)

[quote]
Should a person with diabetes fast?
People who have their diabetes under control, either by their diet or using tablets, may fast. However, their GP may require them to change their medication to help them take tablets outside fasting times. Those who need insulin to control their diabetes should not fast.
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My mother and brother both are on insulin..mom fasted for two days but somehow instead of her sugar levels going down they were quite up by the end of the day, so she stopped. Bro is still continuing, although we keep telling him he doesn't have to but he says that as long as it doesn't effect him adversely he'll try. Does anyone know if there are any non apparent side effects/harm that can be caused if someone on insulin continues to fast?