I want my naturally curly hair back!?

I used to have naturally curly hair and now they've straightened out and look limp. I want my curls back but without using any harsh chemicals. Is it true that curly haired people have more sulphur in their body?! If that's the case should I be eating highly sulphuric foods? Someone told me about increasing my egg intake, but I would much rather prefer taking an edible sulphur based food like a tablet or powder etc. I don't like eggs! Or maybe this change has something to do with ageing?, as I’m getting older, I’ve noticed my hair are thinning and limp, is it hormones? Hope you guys can help me out here! Thanks :)