The fasting month of Ramadan is the ninth lunar month of the Islamic calendar. It is the most important month for Muslims because in which the Qur'an was revealed, and they abstain from food and drink from dawn to sunset to express their gratitude to God. Eating and drinking is permitted only at night, and Muslims typically eat two meals each day, after sunset and just before dawn. People tend to stay up late watching TV with the family, praying or reading the Qur'an. Ramadan teaches Muslims self-restraint and reminds them of the feelings of the impoverished.

On the other hand, the biological effects of changes in lifestyle during Ramadan may also be expected. Some studies have reported substantial weight loss, signs of dehydration, raised serum concentrations of uric acid and cholesterol, etc. during Ramadan. However, these changes are unlikely to have much effect on healthy individuals, because generations of Muslims have undertaken fasting year after year. In conclusion, the observance of the Ramadan fast may produce some ill-effects in patients with some disease, e.g. hypertension, hypercholesterolaemia, hyperuricaemia, hyperglycaemia, and heart, liver and kidney disease.


Sources - https://pubmed.ncbi.nlm.nih.gov/10714147/