Calorie asorbtion

Can anyone tell me what percentage, if any, does the tummy aborb of calories? I have heard that we do not asorb all of our intake of calories, then have been told we do asorb all of them. I am over 5 years post op and am now concerned with calories. Hugs and Love, Marilyn

Good question, I'm concerned about calories too. I hope someone has an answer.

Marilyn My RNY was proximal - so i'm guessing this applies in a proximal RNY case. It might be different for other surgery types. I asked my surgeon about this at my last appointment. He told me that i absorb approximately 20% less. My nutritionist further told me that if I consume 1000 calories, I would only absorb about 800 of those calories and about 80% of the nutrients - the exception being what nutrients that are normally absorbed in the deuodenum - since the deuodenum is bypassed, those nutrients would not be absorbed and would have to be taken in an alternative form (like sublingual B-12). I'm interested in hearing what others have heard.... Pam

I think there is no real way for any of us to truly know except perhaps to micro-manage our own intake and see how our weight goes but then again there are so many outside factors that effect weight too. I know that distals will absorb less than a proximal calorically. We all malabsorb our vitamins and minerals because of the bypassing of the duodendum. I know that if not given enough nutrition, the intestines with hypertrophy (grow) aka lengthen in an attempt to absorb more. I've heard it can even grown a foot or more. Within that additional intestines, vilia develop (fingerlike projections) in an attempt to catch fuel as it flows on through. So, for some, if the intestines did hypertrophy - on paper anyway, they might absorb more than someone whose intestines didn't. So, as you can tell there are many factors that go into this. Pam did give you an idea of what she was told... 20% for a promixal. Sounds fairly logical and reasonable. You might want to do metabolic testing. Often personal trainers, doctors, even chiropractors have the equipment. Hubby and I did it through a trainer here. The technology is by a company I believe called New Leaf. Think they have a website newleafsoftware.com that allows you to enter a zip code and find someone who has the equipment near where you live. Anyway, they measure RMR (resting metabolic rate) as you relax and wear a mask and simply breath. Then they measure your basal metabolic rate on a treadmill while wearing the mask. The RMR is the calories that your body needs to fuel the brain and cells. The BMR is what you burn on a daily basis. If you eat that much, you would maintain your weight. Anything between the RMR and BMR would be a caloric deficit and could lead to a loss. But then again, we have to consider percentage of calories not absorbed into the picture too. So, one could probably intake more than these ranges and still have the same effect. I do not count calories much so I cannot tell you if these values seem truly accurate. If you exercise, the ranges go up by the amount you burn. Hope that made sense. Kathy

Hi, I tried the website you provided, but I don't think it's the correct one for what you're talking about ... Instead, try this one: http://www.newleaffitness.com/ with this next one specifically about the metabolic test: http://www.newleaffitness.com/met-7_metabolic_testing.htm Hope that helps! Carol

Thanks for the correction. Appreciate that. I was trying to remember off the top of my head. Kathy

As a pre-nursing student taking a course in physiology, this is what I know about calorie and nutrient absorption: Digestion begins in the stomach when gastric juice (hydrocloric acid, pepsin, and gastrin) mixes with the food we ingest. This mixture of food and gastric juices is called chyme. The chyme is then "pushed" into the duodenum. Bile, another important component in digestion, is introduced to the chyme in the duodenum. About 95% of ALL absorption occurs in the duodenum - the first part of the small intestine. How much of our intake is absorbed post-WLS depends on many factors: how much of the duodenum was bypassed, how well are you chewing your food, do you drink with meals, what form are you taking your nutrients, how far post-op we are, etc. It would be difficult to give a blanket percentage of what is now absorbed. That's why getting your lab work done on a regular basis is SO important. If you are too low or too high on some nutrient, you can then make the necessary adjustments. I don't know if this exactly answers your question, but I hope it helps. XOXOXO, Sharyn

I am learning more and more...as a senior grad I should know all this excellent info, but some of it was not available when I had WLS.. or I just forgot it. I appreciate your post. It does help me... Hugs and Love, Marilyn

Count on absorbing *every* calorie from sugar and other simple carbs that you put into your face. Sugars and simple starches begin to be digested in the mouth, by an enzyme called amylase. Don't count on absorbing *any* protein, vitamins and minerals from food. We have bypassed digestion and duodenum, which is primary absorption site for these things. We need to take them in "pre-digested" forms now; protein shakes, vitamin/mineral capsules. Count on absorbing *some* fat. This one depends on how long your bypass was, how long it still is (how much it's grown back!), whether your liver is working fine, what kind of fat it is (emulsified is better absorbed), and all kinds of variables. Only you and the toilet know how much. Good luck! And don't worry about calories - worry about getting enough nutrients, in a form you can absorb, AND on not getting any sugar.

Rachel, thank you. I think I mentally count calories still...its a history with me since birth. As well as with some others I have an addition to carbs, its so freaking hard to eat protein, protein and more protein. The sugars tend to still bother me, ie: dumping,naseau, hypo reaction, altho I sneak some in a small portion. Thank you for your post. it helps. Hugs and Love, Marilyn