are probiotics bad

Are probiotics bad in any way? Millions of people use probiotics. They are everywhere. Drug stores and marts are filled with different brands of probiotics. Many assumed they are only beneficial and have no downside.

In a recent study by Rao et al in Clinical and Translational Gastroenterology30 patients with gas, bloating, brain fog and negative tests were compared to 8 patients without brain fog. All the patients with brain fog consumed probiotics. The brain fog group had more small intestinal bacterial overgrowth as well as D-lactic acidosis.

After discontinuing probiotics and completing a course of antibiotics, 23 of the 30 patients reported that their brain fog was resolved as well as their gastrointestinal symptoms.

The conclusion is that probiotics can also promote growth of bacteria in the small intestine and not just the colon. In addition, they can break down sugar and produce D-lactic acid. The brain fogginess come from the D-lactic acid.

This is a small study and the findings need to be confirmed in larger studies.

In a separate study published in Cell, probiotics did not change gut bacteria in some people. Meaning that some people may be resistant to the supplements. In another study, the group found that taking probiotics after use of antibiotics may delay the return of people’s normal gut microbiome. This finding is contrary to the common advice of using probiotics with or after use of antibiotics.


What are probiotics, prebiotics and synbiotics?

Probiotics are live microorganisms that are intended to have health benefits. They are found in fermented food like yogurt, kimchi, sauerkraut and kombucha. However, most probiotics are sold as supplements that do not require FDA approval.

Prebiotics are not live microorganisms. They promote growth of probiotics. They are soluble fermentable fibers that get to our colon undigested. They provide food to the bacteria in the colon and are fermented into short-chain fatty acids.

Synbiotics contain both probiotics and prebiotics.

When are probiotics beneficial?

According to a detailed analysis published in the American Journal of Gastroenterology, there are few strong evidence for the use of probiotics. Some evidence exist for their use in certain conditions. These conditions include using VSL#3 for maintaining remissions in patients with pouchitis or treating active ulcerative colitis, using Lactobacillus in patients with painful diverticulosis, using a variety of probiotics (Lactobacillus, Bifidobacterium, Streptococcus, or VSL#3) in patients with minimal hepatic encephalopathy, or providing synbiotics to patients postoperatively after liver transplantation.

What should you do? 

If probiotics are helpful to you, continue to take them. If you’re taking probiotics and have brain fog and bloating, contact your physician. Brain fog and bloating can be caused by probiotics among other things.


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