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Imbalances in the microbiome can lead to serious health issues, but probiotic-rich foods are the best way to balance your gut health.

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The labels promise a range of benefits: digestion support, reduced gas and bloating, immune system health and the restoration of balance in the body. Probiotic supplements have become a staple on drugstore shelves. But should they be a staple in your diet? Experts say you may be better off to trust your gut.

Probiotics are live micro-organisms that can provide health benefits when consumed in adequate amounts. People consume probiotics through natural sources in fermented foods like yogurt, kimchi, sauerkraut, kefir and kombucha tea. They are also sold in supplement form such as pills, powders and gummies. Probiotics work to create a balance in the gut to support digestion, the immune system and overall health.

The jury is still out as to which probiotics are helpful to prevent or treat specific health problems. If you are healthy and eat a well-balanced diet, you likely have a good balance of gut bacteria with no real need for a probiotic supplement.
Diane Riccardi, Clinical Dietitian

“Our gut microbes appear to play a large role in our health,” explained Diane Riccardi, a clinical dietitian at Moffitt Cancer Center. “But the jury is still out as to which probiotics are helpful to prevent or treat specific health problems. If you are healthy and eat a well-balanced diet, you likely have a good balance of gut bacteria with no real need for a probiotic supplement.”

Research shows that having many different types of gut bacteria ― known as having a diverse microbiome ― is associated with more healthful aging. However, a recent report in The Washington Post points out some studies have shown that people who take probiotic supplements for general health or as a balance to antibiotics can end up with a decreased diversity of microbes in the gut.

“Because each person has a unique community of microbiota, even high-quality probiotic supplements can have different effects in different people. So taking concentrated doses of a few strains may inadvertently crowd out the wrong microbes,” Riccardi explained.

How Gut Health Affects Overall Health

Imbalances in the microbiome can lead to serious health issues.

“Accumulating evidence supports the role of the gut microbiome in several chronic diseases and across the cancer continuum both for prevention and support of cancer therapies,” Riccardi said. “As the composition of these microbes are susceptible to change, an imbalance in the microbiome may lead to disease, including cancer at sites both in and outside of the gut.”

Doratha A. Byrd, PhD, Moffitt Cancer Center

Doratha A. Byrd, Ph.D., Cancer Epidemiology Program

Moffitt researcher Doratha A. Byrd, PhD, is investigating the role of the gut microbiome in cancer development and the response to treatment. Byrd, an assistant member in the Cancer Epidemiology Program, is researching whether the gut microbiome is associated with tumor recurrence and survival among colorectal cancer patients. She also has ongoing studies into associations between the gut microbiome and its metabolites and colorectal cancer risk.

“We hope that these studies will support understanding of how to target the gut microbiome to reduce risk for cancer and to improve cancer outcomes,” Byrd said.

Researchers are also studying how probiotics could play a role in cancer care and prevention. “A few clinical trials show that probiotics can improve the intestinal environment by stimulating the immune system, inhibiting growth of pathogens and reducing metabolism of cancer-causing substances,” Riccardi said.

Achieving the Right Balance

The best way to maintain a healthy gut microbiome is to consume a combination of probiotic-, prebiotic- and polyphenol-rich foods, Riccardi says. Examples include:

  • Probiotic foods ― These include fermented foods such as dairy products (yogurt, kefir, buttermilk, aged cheeses), soy products (miso and tempeh), tea (Kombucha), and vegetables (sauerkraut and Kimchi). Look for product labels that indicate the food contains “live” or “active cultures.”
  • Prebiotic foods ― Fiber-containing foods are rich in prebiotics, which promote the growth of good bacteria in the gut. These include vegetables, nuts, seeds, beans and whole grains.
  • Polyphenol-rich foods ― Colorful plants get their vibrancy from antioxidants called polyphenols, which act like rocket fuel for the beneficial bacteria in the gut. These foods include rainbow-colored fruits and vegetables, as well as beverages like green tea and coffee.

“Balance can best be achieved by consuming probiotics through whole foods that deliver other essential nutrients like fiber, vitamins, minerals and antioxidants that are not obtained through supplements alone,” Riccardi said. “Essentially, every time you eat, you are not just nourishing your body but in fact feeding your microbiome.”


  • If you are thinking of adding a probiotic supplement to your diet, speak with your health care provider first, especially if you have a serious health condition.
  • If you have been prescribed a probiotic supplement, select a multi-strain blend or choose a product containing specific strains that have been clinically tested to help with your health condition.
  • Most supplements have a limited number of bacteria strains, and potency at the time of purchase is not guaranteed as the Food and Drug Administration loosely regulates supplement claims and labeling. Be sure to check the expiration date and follow instructions for storing the product.