how do you gain weight?

My man has been going through a lot lately, and with all of it has lost weight. He is probably going to have an ileostomy soon and I would love it if he really packed on the pounds before he did this. He looses so fast. He doesn't want to eat because eating leads to pooping, and pooping is currently the enemy. He eats about 2 meals a day of his concoction of food that goes through and comes out easiest, but that food is not very high in fat or calories. He does some added peanut butter snacks occasionally and drinks ensure but its high in sugar (he's had a subtotal colectomy so sugar is not good for him). He doesn't care for the kind that are low in sugar (I think they are called glycerna). He is happy with the way his body looks, and don't get me wrong, Im happy with it too. I just want him to bulk up before his next big operation. What do you use to gain weight?

There is a great book called Cooking Well for the Unwell. When I had my ileostomy, I didn't want to eat at all. This book was immensely helpful and it was in my library.

Also, try little things like buttering bread, whole milk (or lactaid), adding a slice of cheese(Cabot or cracker barrels if lactose intolerant) to breakfast sandwiches, mixing peanut butter into pancake recipes and other baked goods.

Good luck!