Villi in the small intestine

I have been told that the villi in the small intestine start to grow after 18 month and food absorption starts to increase again.  Does anyone know of any research which might tell us how to deter this?

I don't think you'd want to deter that. If you never started absorbing calories you'd just keep losing and I would think eventually die. You'd wilt away to nothing. We need to eventually start absorbing again. That way our body can reach a healthy and happy place.

Actually, you're mistaken. The RNY bypasses very little of the small intestine, so even in the very beginning you're only malabsorbing a small per centage of the calories you take in. I don't have any numbers for the per centages of protein and carbs for RNYers, but there was a study that measured the absorption of fat. 'Normal' people absorbed 92%, RNYers absorbed 62%, and DSers absorbed a whopping 19% of dietary fat.

DSers, who in comparison to RNYers have a HUGE amount of small intestine bypassed, generally absorb about 50% of proteins, about 60% of complex carbs, and everybody absorbs nearly 100% of simple carbs, alas. (*grin*)

It's my understanding that they start regrowing right away, and around 18 months is when malabsoprtion of calories mostly stops.  You can't really stop this, it's just a natural part of the body adapting.

If you are asking how to prevent weight gain as your body works toward more normal absorption, it will just be a balancing act.  Watch your intake and your weight.  If you start to see a gain, look at either cutting back intake or increasing activity. 

Your body sees WLS as a traumatic injury, and does its best to 'heal' from it. One way it does this is to grow more villi, to replace the ones that were in the part of your intestine that was bypassed. (Sometimes, your un-bypassed intestine actually grows longer, too!) There's nothing you can do to stop this, and everyone's body has its own rate of effectiveness at 'healing' from WLS.

But keep in mind that this does NOT mean you're going to be able to slack off on your vitamins and supplements. Micronutrients---in other words, vitamins and minerals---are only absorbed by specific receptors. You will ALWAYS need to supplement.