I'm 17, 6 foot 1, And weight around 160 pounds, Which should in my opinion make me look a ok weight, But my arms are really skinny, So are my legs and neck. I've tried to put on weight but it just goes to my belly and does not Distribute its self. I do weights three times a week, Yet my arms or chest do not grow, I eat 5 times a day. I need help, Do I have a underlying Illness or something?.