How much is enough???

I guess your friend feels that what he is doing with regards to fasting is not enough for him to show sacrifice. There are certain people who does that and I think your friend is one of those. It's only natural that you are worried for him because you are his friend. But you can only do so much for your friend. I think he knows that you are thinking of him but it's just his way and his decision why he's doing it.

There is something you should remember about Ramadan. The fasting is only from sunrise to sundown. It is traditional to fast during the daylight hours, then go home to a good meal after sundown. It is also against tradition to harm one's health by fasting at this time. You don't say whether he's observing the usual fast or extending it farther in some way.

Hi, I understand that you are anxious about your friend's health. Actually I have friends too who fast during this time and they firmly believe in serving God through it. I have never seen anyone falling ill or causing harm to their health through fasting. We cannot do anything about the religious beliefs of others. We have to respect their sentiments. I think your friend has already been doing this for some years and he is used to it, right? So do not worry my friend. He will be alright. He is doing what everyone in his religion follows. He cannot give a break certainly.