An emerging body of research is looking at whether propolis can be helpful to the gut microbiome.

According to the aforementioned review in Nutrients, propolis may help protect the gastrointestinal tract by inhibiting the growth of pathogenic bacteria.

How does it do that? Stacie J. Stephenson, a doctor of chiropractic and the chair of functional medicine for Cancer Treatment Centers of America, points to a study published in Biomedicine and Pharmacotherapy in October 2019 that found propolis improved the balance of bacteria and yeasts in the gut microbiome by strengthening the mucosal barrier, which might prevent or heal leaky gut.

“That means it strengthens the barrier that separates your digestive tract from the rest of the body, so that it can let nutrients in and out, but not toxins or food proteins,” explains Dr. Stephenson, the author of Vibrant: A Groundbreaking Program to Get Energized, Own Your Health, and Glow.

It’s important to note that this study was done in diabetic rats, and the results may not be the same in people. “Interestingly, other studies have shown that bee propolis encourages beneficial bacteria and stabilizes the microbiome of honey bees,” Stephenson notes.

In humans, clinical trials, such as one described in August 2020 in Trials, are underway to determine if bee propolis can help people with irritable bowel syndrome (IBS). Until more research is complete, it is too soon to say if propolis has benefits for the human gut microbiome.

The safety of bee propolis hasn’t been widely studied, but it’s generally considered safe for most people in moderate amounts, Stephenson says. “That being said, the FDA has not weighed in on what a ‘moderate amount’ is, and recommendations on products and from various holistic health professionals vary widely,” she notes.

The standard dosage for an adult is about 400 to 500 milligrams (mg) daily in supplement form, Stephenson says. “More is probably safe (some people take therapeutic doses of 2,000 or 3,000 mg per day) but I would only recommend that under the guidance of a holistic health practitioner,” she says.

Stephenson notes that some people may be allergic to propolis, and advises speaking to your doctor before taking it if you have allergies or asthma or are worried about an allergic reaction.

Additionally, she advises caution for people with cancer who are interested in using propolis for its supposed anti-cancer effects. “Claims about bee propolis as a miracle cure can sound convincing, but there isn’t any really good evidence to show that bee propolis will actually affect tumor progression in a person,” Stephenson says.

She points to a case of a cancer patient who took large doses of bee propolis, which led to a toxic effect on kidney function. “If you have any serious chronic disease, get your doctor’s okay before taking bee propolis, and get guidance on the right dosage for you,” Stephenson advises.

If you’re interested in trying bee propolis, it’s available in many health food stores. It comes in many forms, though it is most commonly available as capsules.

“In addition to capsules, you may be able to find it in lozenge, powder, and cream forms, or even in mouthwash and toothpaste,” Stephenson notes.

It’s also sold as spreads mixed with other bee ingredients such as honey, royal jelly, and pollen, Samanci says. For safety, she recommends checking the product label and making sure the amount of propolis is indicated.

Stephenson also advises looking for a manufacturer you trust, who uses third-party verification for purity. “Supplements are still not nearly as closely regulated as medications, so it’s beneficial to research companies before choosing any supplement products,” she says