During the last year or so, I've dramatically changed my diet. I never used to have a taste for many vegetables, and recently, I've developed a taste for them. I used to replace entire meals with things like cookies or potato chips, and have totally cut out behavior like that, and have dramatically cut the amount of junk I eat in general. Due to this, over the last year, I grew about an inch and lost 2 or 3 pounds. Just one problem. I'm now 6'3" and I weight just over 150 pounds. It's scary, some of my pants that used to fit me fine without a belt I now need a belt for. But what am I to do, start eating massive amounts of junk again and give up low-calorie things like vegetables? Besides working out to build muscle mass or eating unhealthily, is there any way a twig like me could gain a few pounds?