Ok Notehook, here's a serious response:

Lack of appetite is one reason a person can get a doctors approval for med mj. This, however, is usually for people that have an illness , and/or are taking medication for that illness, that causes them to lose their appetite. It's not so much as something to help them gain but something to help them stop losing. My Mom was recently on chemo for cancer (she's fine now) and she lost a lot of weight because she was nauseous all the time. She didn't want it but I'm sure she could have gotten medical marijuana if she did.

So, if you're sick and have lost a lot of weight cause the docs gave you some drug that makes you not want to eat you are a good candidate for med mj. If you're just skinny and aren't really into eating that's a different story.