Why You Should Consider Taking A Probiotic After WLS

You might have heard that gastric bypass and other weight-loss surgeries can change the types and quantities of bacteria normally found in the gut. Bacteria in our gastrointestinal tracts are essential for many functions, including helping to digest food, absorb nutrients, and keep away harmful bacteria.

Surgeries like gastric bypass can reduce the number of beneficial bacteria in the gut and can lead to problems such as harmful bacterial overgrowth and restricted movement of the muscles which help move food through the stomach and intestines. Not only can bacterial overgrowth happen as a result of reducing the size of the stomach and intestines, but also because of a reduction in stomach acid which normally helps keep bad bacteria at bay. These patients can experience symptoms of discomfort such as upset stomach, bloating, gas, and diarrhea.

In combination with the reduced size of the stomach (and subsequent reduction in intrinsic factor needed to absorb B12), the bacterial overgrowth that can result from WLS can break down vitamin B12 before the body has a chance to absorb this essential vitamin. As a result, gastric bypass patients are at increased risk of vitamin B12 deficiency even if they are taking their B12 supplements!

Benefits of Taking a Daily Probiotic After WLS

Probiotics are made up of good bacteria normally found in and on our bodies as well as in foods such as yogurt. Unfortunately for the yogurt-lovers out there, the exact amount of probiotics in yogurt is oftentimes unknown and is presumed to be a very small amount. Supplementing with an oral probiotic has been proven safe and can help post-WLS patients in many ways including:

  • Reducing bacterial overgrowth and improving immune function by restoring microbial balance and replacing harmful bacteria (like E.coli) with beneficial bacteria
  • Relieving uncomfortable symptoms such as abdominal pain, bloating, gas, and diarrhea
  • Maintaining vitamin B12 levels by reducing harmful bacteria that destroy vitamin B12 before it can be absorbed
  • Improving digestion, especially of protein, by enhancing the movement of muscles and production of mucus that help move food through the gastrointestinal tract
  • Reducing the chance of developing an infection after surgery which occurs in 10-30% of patients after WLS
  • Reducing inflammation (or swelling) after surgery
  • Increasing weight loss. Studies have shown that patients who take a probiotic alongside their other vitamin supplements after WLS lose more weight more quickly as compared to patients who do not take a probiotic.

As always, make sure you talk to your doctor or pharmacist before starting any new medications or supplements, including over-the-counter and herbal products.

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  1. Woodard GA, Encarnacion B, Downey JR, et al. Probiotics Improve Outcomes After Roux-en-Y Gastric Bypass Surgery: A Prospective Randomized Trial. J Gastrointest Surg. 2009;13:1198-1204. doi:10.1007/s11605-009-0891-x.
  2. Jeppsson B, Mangell P, Thorlacius H. Use of Probiotics as Prophylaxis for Postoperative Infections. Nutrients. 2011;3(5):604-612. doi:10.3390/nu3050604.


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