Hi I'm An 18 year old female, I'm 6 stone and I look & feel so thin I want to gain weight but I just don't know what to do. Should I see a doctor?

Oh, that's perfectly normal! I'm 19 and I weigh around 90 pounds. That's 6.42 in stones. It may be that your metabolism is extremely fast. Or, if you really are worries, do go to a doctor if this has become a fairly recent problem.

Don't know what a stone is. Judging by the above post, it would seem you're under 100 pounds. That's pretty thin.

See your doctor if you're eating healthy and not putting on weight. It could be an imbalance.