Hi, Mary.

I hope you are doing well in every way now.

Yes; it's very common to lose 20 pounds (or more) at about a month post op. You will probably lose a bit more, too--but, I don't advise intentionally going on a weight loss diet at this time, unless you are under medical supervision. You are still healing in many ways. And, if you are have a j-pouch, it won't long until your next surgery. You'll want to be be in optimal nutritional status for another go 'round of healing!

There are several reasons for rapid weight loss after a colectomy (I'm assuming that's why you have your ileostomy...)

For one, UC patients (and some Crohn's patients) usually get to wean off steriods after having a colectomy. (Yea!) By the time they are a month or so post op, many, esp the UC patients, are typically steriod free, and therefore, free of the "fattening" side effects of steroids, like ravenous hunger and salt retention. 

For the first few days post op, you didn't eat at all, were on clear liquids, or ate very little. THAT dropped off a few pounds...

Then, if you were like most folks, you were rather tentative about eating, being scared that anything might hurt--or get stuck-- going down, in the middle, or on it's way out! So, you were experimental and picky about what you would try. THIS took off a few more pounds...

You learned something about good digestion that people without ileostomies are told all time (but just don't seem to want to heed)--eating six small meals a day is very good for you! It's more satisfying, too, so overall, you tend to eat less. Say "bye bye" to a few extra pounds...

And, surprise! Taking small bites, and slowly and carefully chewing your food, not only lessens the likelihood of ostomy troubles "down the line," but causes you to think about what you're eating, make better food choice decisions. You also feel fuller sooner, and don't scarf down a whole lot of junk, that you don't even remember you ate, in just a few seconds. So, presto! The pounds have disappeared!

Hope