Some info on sleep, hormones, and hair growth
Hair growth depends on several factors. Getting enough sleep is one, according to the Proctor and Gamble website. Hair grows faster in one's sleep, and so making sure to get to bed on time and sleeping at least seven hours a night will help hair grow faster. Having the correct balance of male and female hormones also plays a role. Male hormone levels will regulate hair thickness and how fast hair grows, while female hormone levels regulate how long hair stays in its growth phase.