Is fasting in Ramadan bad for your health?
Not for a healthy person. The body copes well with fasting, and it does good to both body and soul. According to the Holy Qur’an, someone who is ill should not fast at all.
In summer a day of fasting can become very long in northern countries. So some people ask whether the kidneys suffer when someone drinks nothing for so many hours. Experience says otherwise. Muslims have fasted in Ramadan for centuries, including in very hot regions, without fasting leading to kidney disease there. The kidneys can take a great deal. After breaking the fast people drink plenty, and the kidneys are thoroughly flushed. That more than makes up for any disadvantage.
What matters is that Islam forces no one to harm himself. The Holy Qur’an says clearly that a sick person does not fast but makes up the days later, once he is well again. For anyone who could only fast with great difficulty there is a substitute, namely feeding a poor person. So someone who, for example, has a sensitive stomach condition and would become ill through fasting is released from this duty.
For healthy people, fasting is rather a gain. Many people eat too much, too richly and too often. A month of fasting corrects this excess. People come out of Ramadan lighter in body and stronger in soul.
And fasting has another side as well. Someone who lives in comfort feels in his own body, for a whole month, what hunger and thirst mean. In this way he understands the suffering of those who have nothing far better than through any book. As the verse above says, the aim is for a person to become righteous, that is, more mindful of God and of other people.