According to the Qur'an and the Sunnah, diabetes is among the illnesses that can exempt a person from fasting. If the person nevertheless wishes to fast, it is recommended to discuss it with the doctor. As is known, diabetic patients treated with insulin who want to fast are particularly at risk, since there is a risk of significant hypoglycemia or hyperglycemia.
If the person who has chosen to fast finds themselves in a difficult situation, they will then be obligated to break the fast, because Islamic law protects the life of the Muslim, which is sacred.
What the science says: fasting, diabetes, and blood sugar
What published research says about the remedies mentioned above, for context — these studies address material causes, while healing belongs to Allah.
Fasting
Fasting, prescribed and then recommended by the Sunnah (Monday-Thursday, the white days), is now studied under the name of intermittent fasting: a meta-analysis in the BMJ shows favorable effects on weight and cardiometabolic risk factors (BMJ, 2025), with an impact on appetite (Nutrients, 2023) and body composition (Diabetes Obes Metab, 2024). Precaution: people with diabetes on insulin, who are pregnant, breastfeeding, or in a fragile state of health must adapt their fasting with their doctor — Islam permits, and sometimes requires, not fasting in case of illness.
Diabetes and blood sugar
Diet (low glycemic index, fiber, fewer fast-absorbing sugars) is the foundation of type 2 diabetes treatment (BMJ, 2021); several plants from tradition — cinnamon, fenugreek, black seed, turmeric, olive leaf — have a blood-sugar-lowering effect confirmed by meta-analyses (Diabetes Metab Syndr, 2023) (Nutrients, 2024), and camel milk is being studied in this context. Precaution: these remedies are in addition to treatment and can cause hypoglycemia if combined with it — monitor blood sugar and never change an insulin dose without your doctor.
