A few years ago, I suffered terrible migraines. My doctor told me that I could not take some medications to stop the pain because I didn't weigh enough. One of the side effects was weight loss and I weighed 106. I tried eating more fatty foods and it didn't work. I ended up with high cholesterol instead. So I changed my eating habits to be healthier and did some research. Have you heard of the Mayo Clinic? The do all kinds of research and try various procedures to treat just about anything. I came across an article on their website about how to safely gain weight. It talks about what your diet should consist of and what type of exercising you should do. I am gaining weight but not exactly where I want to be yet. But I do feel a lot better and my butt looks good.
You don't want to gain weight in an unhealthy way. Try these tips from the Mayo Clinic. It just might work for you as well.
Too skinny? How to add pounds safely - MayoClinic.com