The Problem with Probiotic Supplements: Are They What They Seem to Be?

mage close up of Probiotic Supplements capsule bottle between the fingers

There’s no shortage of supplements on the market, and sales of pills and capsules that promise health benefits are brisk. However, when you buy a supplement, you don’t know for sure what you’re getting. That’s because the supplement industry is largely unregulated. A manufacturer can place a supplement on the market without getting the FDA’s approval. In contrast, pharmaceuticals undergo extensive testing in the laboratory, in animal studies, and in people before their release. Even then, medications enter the market that later prove to have unforeseen side effects and risks.

One of the most popular supplements, at the moment, are probiotics. The fascination with probiotics is largely due to a strong focus on the gut microbiome as a key element in health and disease. If you don’t know, probiotics are bacteria that are beneficial to the large intestinal tract. Unlike bacteria that cause illness, probiotic bacteria help keep the lining of the gut healthy by holding foreign invaders at bay, by boosting immune health, and by keeping the lining of your gut healthy. Who doesn’t want a healthy digestive tract?

Why is there so much focus in this area? Preliminary research suggests that probiotics may improve some aspects of digestive health. For example, antibiotics eradicate good bacteria as well as bad, and one of the side effects of many antibiotics is diarrhea. Fortunately, research shows that taking probiotics may prevent or reduce the severity of diarrhea in people who take antibiotics. Probiotics may also be beneficial for people with inflammatory bowel conditions and functional bowel issues, like irritable bowel syndrome. In addition, researchers are exploring the role probiotics play in immune function and whether they lower the risk of developing some types of infections. There’s also interest in whether probiotics might also keep tissue from damaging inflammation.

Who wouldn’t want these benefits? In hopes of getting them, more people are turning to probiotic supplements or “bacteria in a pill.” It sounds so simple! Swallow a capsule to get the potential benefits of probiotics. However, as mentioned, the supplement industry isn’t regulated and this raises the question. Are you really getting enough probiotics when you take a supplement to get benefits?

What’s Are Probiotic Supplements?

In one study, researchers tested 17 different probiotic supplements by doing a DNA analysis to see what strains and how much was in the various probiotic products. They also used a testing protocol called PCR, or polymerase chain reaction, to verify the particular species of bacteria in each supplement. Although the samples they tested were consistent between samples in the same lot, the bacteria in the samples didn’t always match what was on the label. Among the samples they tested, 12 had strains listed on the label that wasn’t in the product and 13 tested positive for strains of bacteria not listed. In fact, only one supplement out of 17 matched its label.

Bacterial Quantities May Not Match What’s on the Label

Some probiotic supplements may contain the strains of bacteria listed on the label, but are the quantities high enough to offer benefits? When Consumer Lab, an independent testing firm, analyzed 18 probiotic supplements, 16 of the 18 contained the number of bacteria listed on the label. Not bad, unless you purchase one of the supplements that fall short. A probiotic supplement should have one billion to 10 billion bacterial cells or colony-forming units if the dosage is one tablet per day.

There’s also the question of product viability. The appropriate number of bacterial colonies may be in the supplement initially, but some may die off over time. Manufacturers sometimes add extra bacteria to compensate for this. If you expose a probiotic supplement to heat, light, or moisture, it can destroy some of the bacteria and shorten the product’s shelf life. So, what you buy might not be what you get.

Why Fermented Foods are a Better Choice

As you can see, probiotics have issues. But, you don’t have to invest in an expensive supplement to seed your gut with probiotic bacteria. Fermented foods, like yogurt with active cultures and fermented vegetables, provide this benefit too. You hear less about them because they come from natural food sources rather than supplements. The reason fermented foods are a better choice in most situations as they contain a diversity of probiotic bacteria. That’s important because we still don’t know which strains are best for each individual and health condition. For example, one strain might be better for digestive health while another best for optimizing immune health.

The most common probiotic bacteria in supplements are strains of Lactobacillus and Bifidobacterium whereas fermented foods may contain a variety of strains. In addition, if you consume fermented vegetables, you also get prebiotic fiber for the bacteria to feed on. Another benefit of fermented foods is the fermentation process pre-digests some of the nutrients in the food, making the nutrients more bioavailable.

Also, be aware that taking a high-dose probiotic supplement isn’t suitable for everyone. If an individual with a weakened immune system takes a probiotic supplement, it could be harmful. There have been rare reports of people developing infections from taking probiotics. These are usually folks who were very young or very old or who had a weakened immune system. That’s why it’s a good idea to check with your healthcare provider before taking a probiotic supplement. If you’re allergic to cow’s milk, it’s best to avoid probiotic supplements since manufacturers often use dairy milk as a substrate to grow the bacteria. Traces of milk protein may remain in the final product.

The Bottom Line

If you take a probiotic supplement, research the brand you’re taking carefully and make sure you’re getting what the label says you are. Also, consider getting your probiotics from natural sources, like yogurt with active cultures, kefir, tempeh, or from fermented vegetables. Fermented vegetables, like fresh sauerkraut, are a particularly good option as they help you meet your vegetable quota and also supply prebiotics to help the probiotic bacteria flourish. Also, consider making your own fermented vegetables at home. You can find instructions on how to do this online.



Examine.com. “Your Probiotic May Be Lying to You”
Consumer Lab. “Product Review: Probiotics”
National Center for Complementary and Integrative Health. “Probiotics: In Depth”
Am J Clin Nutr February 2001. vol. 73 no. 2 374s-379s.
Today’s Dietitian. Vol. 13 No. 10 P. 46.


Related Articles:

Fermented Foods vs. Probiotic Supplements: Is One Better Than the Other?

Are Probiotic Supplements Overhyped?

Can Probiotics Help with Exercise Recovery?

Probiotics: Can Friendly Bacteria Help You Lose Weight?


Hi, I'm Cathe

I want to help you get in the best shape of your life and stay healthy with my workout videos, DVDs and Free Weekly Newsletter. Here are several ways you can watch and work out to my exercise videos and purchase my fitness products:

Get Your Free Weekly Cathe Friedrich Newsletter

Get free weekly tips on Fitness, Health, Weight Loss and Nutrition delivered directly to your email inbox. Plus get Special Cathe Product Offers and learn about What’s New at Cathe Dot Com.

Enter your email address below to start receiving my free weekly updates. Don’t worry…I guarantee 100% privacy. Your information will not be shared and you can easily unsubscribe whenever you like. Our Privacy Policy