Probiotics and arthritis

Adding fermented foods to your diet may be a better way to incorporate probiotics than taking supplements.

Probiotics are increasingly associated with numerous health benefits, and some studies even hint at a possible beneficial role for probiotics in people who have rheumatoid arthritis (RA).

So what exactly are probiotics? The most widely used definition comes from the Food and Agriculture Organization of the United Nations, which calls probiotics “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.” This official definition adds that, to be effective, probiotics must be consumed in sufficient amounts in food.

How the Bacteria in Your Gut Actually Works

Your gut is teeming with both good — and not-so-good — bacteria. “The presence of good bacteria in the gut (and other body locations) prevents the overgrowth of bacteria that can cause disease,” says Ana-Maria Orbai, MD, assistant professor of medicine in rheumatology at Johns Hopkins Medicine in Baltimore.

And probiotics can play a role in gut health. According to Dr. Orbai, “Probiotics are live bacterial supplements administered to introduce or supplement live good bacteria to maintain a healthy equilibrium between different types of bacteria in the gut.”

RELATED: Gluten and RA: Any Connection?

The idea that microorganisms in the gut (the gut microbiota) may be involved in the development of rheumatoid arthritis has been established in animal studies, and some researchers suspect a disrupted microbiota may prime the human immune system to misfire and cause RA.

For example, one study published in 2013 in the journal Elife found that patients who were recently diagnosed with RA — but hadn’t yet begun treatment — had higher amounts of the intestinal bacteria Prevotella copri (P. copri) compared to healthy people. P. copri trains the immune system to produce a certain type of cell, which releases molecules that “cause inflammation and bone damage in arthritis.” But RA is a complex disease, and this finding does not mean that P. copri actually causes RA.

Does Probiotic Therapy Help With RA?

According to the Arthritis Foundation, probiotics work in three ways: They maintain the balance of good and bad bacteria in the body, reduce the amount of bad bacteria that causes infection and illness, and replenish good bacteria after an illness or round of antibiotics depletes them.

If, in fact, the balance of good and bad gut bacteria is disrupted in patients with RA (or other inflammatory diseases), researchers hypothesize that probiotics may normalize the gut bacteria and, in turn, help alleviate RA symptoms.

“In a small blinded randomized control trial, 46 patients with RA were treated with Lactobacillus casei [naturally occurring “good” bacteria] versus a placebo. Patients taking Lactobacillus had improved disease activity and inflammatory markers [substances that indicate inflammation],” says Dr. Orbai.

RELATED: Can a Vegan Diet Help Your Arthritis?

“In a different, small blinded randomized control study with another probiotic (a mix of two types of bacteria), 30 study subjects showed no difference in disease activity, inflammatory markers, or physical function — and in this study, changes in RA cytokines [small proteins involved in inflammation] favored the placebo,” says Orbai. Therefore, there is no solid evidence for probiotic therapy in RA, says Orbai.

Another problem with these trials is that preparations are not standardized, so direct comparisons are not possible, she adds.

To date, there are few human studies with probiotics in people with RA, and most, such as the ones Orbai cites, are based on very small sample sizes. The inconclusive results make it difficult for practitioners to draw sound conclusions or make recommendations to patients.

Probiotics and RA: The Bottom Line

Eating a healthy diet helps you maintain a good balance of bacteria in your gut. It also strengthens your immune system, preventing bad bacteria from escaping the intestines and entering your bloodstream where it may trigger an inflammatory response. Adding fermented and other foods supplemented with probiotics to your diet, such as sauerkraut, tempeh, kimchi, kombucha, kefir, and especially yogurt, may be a better way to incorporate probiotics than taking supplements.

Another reason to try to get your probiotics from food is that, in addition to the lack of sound research on probiotic supplements, they also aren’t regulated — so you have to be careful when purchasing them. The Arthritis Foundation encourages you to look for supplements with a USP label (U.S. Pharmacopeial Convention), which indicates that a third party has verified the ingredients.

And be sure to check with your physician before taking probiotics. “There may be risks,” says Orbai, “since there are millions of live bacteria that make it into the gut artificially. The risk will also depend on individual factors. Some people can also experience gastrointestinal discomfort [from taking probiotics].”