Most of "certified trainers" recomend 1-1.2g times ur body weight. Personally, I go 2 times my wieght. So if u weight 200lb, I would go 400 g
protein a day, and textbooks recomend u to take around 200g
protein a day. But it's all depends on what ur acitiviy lvls r and how often u lift and stuff liek that.