Common Side Effects of Probiotics: Should You Worry?

Filed Under: Digestive Health, Gut Bacteria & Probiotics, Probiotics

For probiotics, side effects can be a sign of effectiveness

For most people, taking a quality probiotic supplement doesn’t have any side effects other than higher energy and better digestive health. But for some—particularly those whose gut bacteria has been out of balance for years—there can be a “transition period” when existing problems, such as gas and bloating, actually can be aggravated.

This aspect of taking probiotics isn't often discussed, which is unfortunate. Many people look at their worsening symptoms and conclude that not only is the supplement not working as expected, but it's actually making their situation worse. Consequently, they stop taking the product before it has a chance to help them.

If you're experiencing probiotic side effects, please understand that while the symptoms may be inconvenient (and, I'll admit, occasionally embarrassing), they also are temporary.

See a list of all articles about Gut Bacteria in the Gut Bacteria and Probiotics Index

The normal pH (the acidity/alkalinity scale) of the colon should be between 6.7 and 6.9. A pH of 7.0 is neutral; anything below that is acidic and anything above is alkaline. To inhibit pathogenic bacteria and encourage the growth of good gut bacteria, your colon needs to be slightly acidic.

Antibiotics, chlorine in the water supply, drugs (prescription and over the counter), and other factors that damage gut bacteria make the environment of the colon more alkaline. When you start taking a probiotic supplement, these newly introduced friendly bacteria change the pH to become more acidic—a much more hospitable environment for them. This can be a struggle in the beginning because the other bacteria are so firmly entrenched.

As the colon’s pH changes from alkaline to acidic and the good and bad bacteria go through their tug of war, some people may begin to experience grumblings, gas, loose stools, or other bowel symptoms.

How long this lasts can vary from individual to individual. For example, if you’re taking antibiotics or other drugs that kill good gut bacteria, the transition could take a long time or may never happen. Common medications such as painkillers, analgesics, steroids, anti-inflammatories, sleeping pills, birth control pills, antacids, vaccines, and many others either kill or interfere with the growth of beneficial flora. If you can eliminate or, at the very least, minimize these drugs, you have a much better chance of restoring your bowel flora to normal.

It also helps to regularly consume fermented foods such as real live yogurt and homemade sauerkraut, and other cultured foods such as sourdough, kefir, kombucha, and buttermilk.

Discontinuing the probiotic may get rid of your transition symptoms, but it won’t give the good bacteria a chance to take over. And worse, you won’t experience the benefits associated with a healthy colon.

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DISCLAIMER: The content of is offered on an informational basis only, and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified health provider before making any adjustment to a medication or treatment you are currently using, and/or starting any new medication or treatment. All recommendations are "generally informational" and not specifically applicable to any individual's medical problems, concerns and/or needs.

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