Aside from hair transplants, there are sooooo many pills, lotions, electric stimulation, caffeine rubs, etc...on the market.
Vitamins such as biotin are said to help. I know some swear by Rogaine (which you have to continue using) and Nutricap.
Gotu Kola and Gooseberries seem to be popular, as well as Ginseng.
There is so much too weed through, and results vary from person to person.
Of course genetics play a huge role and you might just waste your money. Your health and diet play a big part, and what abuse have you put your through too.
In some cultures, they shave their child's fine baby hair believing that this will thicken the new growth.
Good luck with your paper, I hope I helped add a word or two.
Sometimes, it is, just what is though.
