re taking a supplement, say from GNC, that purports
to increase testosterone, first, it might not actually do that, second it might not have in it what it says it does, and third, the amount of increased testosterone from supplements can help with energy but probably not do what you think it does -- and this is in addition to the above correctly noting that it isn't good for you. It also won't make you lose weight if your diet isn't a good diet for you.