It's strictly personal (with people and females in particular), like I don't feel "good enough" although I really don't have anything less than others. It's just that some days I feel very very confident, but it happens like 3 times a year...are these confidence issues: work, school or personal (females)? a lot of it has to do with just being gung-ho about it and speaking confidently. to speak confidently, just take out the bullshit on subject matters.
but, no matter how many supplements you take -- if you don't practice it -- it won't ever come naturally, imo.
Although I practice (I do, believe me), it's just that there's always this feeling and I believe that some substances (mainly nootropics I think) can help this. Not solve, obviously, but help.
Also, nootropics are always welcome, let's say I'm interested in improving myself in general. I am in Med school and nootropics to help memory and attention (I tend to have a very short attention span) are very useful, but I'm really new to this world... I'm reading a lot about them in this board!