Is it okay to eat doughnuts before swimming?

I guess it depends on how many :)

My opinion, maybe 1 at the least, with the amount of sugar and deep fried oil those things are fried in, it will slow you down and make you get a horrible stomach ache and kot feel well if you eat too much period. Swimming works almost every core of the body, so you don't want to prohibit your bodies movement with sugars and fats

Of course that's fine! Just don't eat too many or you might sink to the bottom of the pool.

Sure