@OGIONIK,
Thanks, CJane - and feel better soon.
Hmm, Ogi, weight gain. Heh, I should just donate you some of mine.
But seriously, you may need to eat more calorically dense foods. Not go crazy with cholesterol and fat, but more calorie bang for the buck than you've been eating. That can translate into meats, cheeses, foods with sauces, again not going overboard with fat.
You want weight but you want it to be muscle mass I take it, so you need to get these extra calories from more protein sources and not so much from fat or carb sources. Think steak versus fettucine alfredo.
Potatoes are fine, so is pasta, just not too much butter in the sauce. You do need carbs, of course (everybody needs all of that stuff), probably would be better to stay away from things that are too refined, like white rice, white grain pasta, that kind of thing. Hope this helps.