Two reasons:

1) often during a severe flare patients voluntarily limit their diets because more food or more varies food tends to mean more pain. Most patients are able to eat a wide variety of foods freely with an end ileo.

2) downstream inflammation can cause fast transit upstream. In other words, colitis can cause food to pass through the small intestine too quickly, leading to decreased absorption of the food you eat. Transit time tends to slow down to normal speeds with the end ileo.

Hope that helps. Anecdotally I didn't gain back all my weight with my end ileo, but I gained about 25 lb pretty easily (as compared to stuffing my face during my flare trying to maintain my underweight size)

Nutrient absorption takes place in the terminal ileum, so as long as it's not compromised, ostomates gain weight just as easily as colonless patients.

Sue

In addition to the above, there is massive protein loss from the diseased colon during active UC. This is why removing the colon results in a reversal of the weight loss, as long as there isn't also ileal disease in a sufficient quantity. There is about 20 feet of small boweo to absorb nutrients (its primary function). Very little nutrient absorption occrs in the colon. The colon's primary function is water absorption.

Jan

Yup and look at it this way: once the diseased colon is gone, you aren't sick anymore. A healthy, healed body will gain weight naturally.

Jan Dollar - why is there a massive protein loss from the diseased colon?

The inflamed mucosa is like a giant burn wound, oozing and weeping. The body tries to manufacture more and more mucus to protect the lining of the colon, and this is shed like rain off a duck. Unfortunately, it contains massive amounts of protein.

Jan

Jan, I have to share this from a biology class in high school.

"Mucus, full of protein. You can swallow it or spit it on your friends." - HS Teacher


Gross, but you know what, I REMEMBERED that mucus is basically protein.

Too funny!

Jan