My brother is having trouble

My 25 year old brother has been having trouble with cumming. Usually he can cum inside of a minute or two but lately it’s been longer, I was wondering if it had anything to do with this:<br>Around January this year, he began fasting for 48 hours two times a week. I started seeing a decrease in semen volume and quality about a few months in. He has also been drinking coconut water and taking a lot of different supplements. Does anyone know if any of these things could be affecting his fertility. He definitely has trouble breeding now, which was not the case before unless he was eating certain food.