I've got a question which is kind of strange.
I need to gain weight, in fact, the story is very very long. (You can read about the whole thing here : http://www.marksdailyapple.com/forum/thread57305.html)
Been through an important weight loss and degradation of my body, at first because of mistakes I made, then because of hypogonadism. Typically, I'm treated and I'm now eating in order to gain weight steadily and slowly. I don't have much muscle mass but it seems to rebuild itself quite well now, I'm even more muscular than when I lifted weights (I can't at the moment though because of my health state), but my bodyfat percentage is also too low, measured around 5% by BIA or 9% by DXA (which is more precise but tends to give higher percentage than what the "internet" thinks, in bodybuilding forums and such...)

So my question is, how much is enough ? My weight is slowly and slowly increasing, and my bf% reading too, I don't look fat at all however, but I want to know if it's possible to be on the lean side without exercise, I'm 18.
My body shape seems to become quite enjoyable as I'm more and more looking like a man, with a good muscular base, but I don't want to blur everything with too much fat. But my health is what matters the most for me so do you have any idea what bf% I should aim for on the long term ?

I've been told that around 8-12%, more 10%-12% for a sedentary teenager, is quite possible.

Thanks =)