Why would vitamins be needed forever after a Vertical Sleeve Gastrectomy?

Hello,
Thanks for your question.
There is no need to take vitamin mineral supplements for after gastric sleeve surgery.  Because the absorption does not decrease after gastric sleeve surgery.  We recommend supplements only because the amount of food consumed in the first 2-3 months is low. On your 3rd month you should make blood test results if there is a deficiency in any vitamin-mineral, then it should be supplemented, but there is no need to use multivitamins
I hope this answer helps you.
Have a healthy day
Dr HE

That’s an excellent and very insightful question. You’re correct that vertical sleeve gastrectomy (VSG) is primarily a restrictive procedure rather than a malabsorptive one, meaning it reduces the size of the stomach but doesn’t reroute the intestines the way gastric bypass does. However, there are several important reasons why lifelong vitamin supplementation is still necessary after VSG.
First, even though absorption is not directly altered, your new stomach is much smaller and produces less stomach acid. This affects the breakdown and absorption of key nutrients such as iron, calcium, and vitamin B12. Many patients also eat significantly less overall, so their nutrient intake naturally decreases. Over time, even small deficiencies can accumulate and cause problems such as anemia, bone loss, fatigue, or neurological symptoms if not prevented.
Second, some patients develop changes in food tolerance or appetite that make it difficult to consume a balanced diet, especially during the first year after surgery. Because long-term nutritional deficiencies can be subtle and take years to appear, consistent supplementation and regular blood work are critical preventive measures.
In short, while VSG doesn’t cause major malabsorption, it still alters the way your body processes and absorbs certain nutrients. That’s why your doctor recommends daily vitamins for life—to ensure you stay healthy, maintain your energy, and protect your long-term results.

Vitamin absorption after sleeve gastrectomy is completely normal for most patients.  There is a drop in gastric acid production (85% of stomach is removed) so an occasional patient may need B-12 shots.  However, after surgery we want patients to shrink meals down to 4 ounces of good protein.  Because you will not be eating the same wide variety of food after sleeve gastrectomy, we recommend an over the counter multivitamin.

While it is true that gastric sleeve does not interfere with normal absorption process, but you may require to take vitamin supplements because you may have a less intake of your normal daily portion of food. Just by the nature of surgery, you will be eating less and thus there is lower intake of vitamins and minerals. Among different weight loss surgeries, lap band and gastric sleeve patients are less likely to require daily supplements.

It is recommeded to take a multivitamin for patients that had a sleeve gastrectomy.  Even though this procedure does not have significant impact on the overall absorptive funcition, the current standard is to supplement your body with these important nutrients to maximize cellular function. Even if you have not had weight loss surgery, I still recommed a multivitamin to make sure sure that your body is functioning optimally.

Almost all of the vitamins and minerals that we get come from our food.  Couple this with the knowledge of what is in the standard American diet and you can see why many experts recommend that EVERY adult take a daily multivitamin even if they have never had weight loss surgery!. 

After weight loss surgery (regardless of what surgery is done), patients take in significantly less food so they REALLY need to make sure they are taking taking their vitamin and mineral supplements to prevent deficiencies.  Although the exact vitamin and mineral regimen that weight loss surgery patients need is still being debated, I think it is fair to say that the need for some type of supplementation is universally accepted.  

With all bariatric procedures a daily multivitamin is necessary. It is true that the sleeve gastrectomy is not a malabsorptive procedure however due to the fact that you are eating 80 to 90% less you may become vitamin deficient.  You may not be able to get enough vitamins in with the small amount that you eat. The LapBand also requires a daily multivitamin for that reason.

Your stomach makes something called "intrinsic factor" which helps with absorption of B12, so with less stomach there is less intrinsic factor produced so you could become deficient in B12.  Since many people walking around today are vitamin D deficient, you can also develop low Vit D levels.  Taking a multivitamin daily after weight loss surgery will help keep your vitamin levels in a desired range.  Getting your levels checked annually by your medical doctor or Bariatric surgeon will help identify any deficiencies and direct appropriate supplementation.