Kefir may offer a number of health benefits, including promoting gut microbial health, helping manage blood sugar and reducing inflammation. Read on to learn what current research says about kefir’s potential health benefits.

Good Source of Probiotics

“Kefir contains various strains of live bacteria, making it a rich and diverse probiotic source,” says Julie Balsamo, a Jackson, Wyoming-based registered dietitian specializing in gut health.

Probiotics are living microorganisms, including bacteria and yeast, that offer health benefits. Some of the potential benefits of probiotics include their ability to alter the composition of bacteria in the gut, improve intestinal barrier function, support healthy digestion and help produce short-chain fatty acids—compounds associated with health and lower risk of chronic disease—and certain vitamins. They may also help modulate the immune system and decrease inflammation.

The gut is lined with different species of bacteria, says Boston-based registered dietitian Alyssa Pacheco, “and more diverse gut microbiomes have been linked to better health outcomes.”

A review of 19 studies examining the effect of fermented foods, including kefir, on the gut microbiota found that these foods help modify the microbial makeup of the gut and may help improve immunity and metabolic factors.

In one small study examining kefir’s effect on gut bacteria specifically, people with metabolic syndrome who consumed 180 milliliters of kefir daily for 12 weeks had a significant increase in Actinobacteria in the gut, improved insulin and lowered blood pressure levels.

May Aid in Blood Sugar Management

Consuming kefir may help manage blood sugar levels, especially in people with type 2 diabetes.

In one small 2015 study, 60 people with type 2 diabetes consumed either 600 milliliters of kefir twice a day or a placebo for eight weeks. Those who consumed the kefir had significantly lower hemoglobin A1c (HgA1c), a measure of blood sugar over time, compared to placebo.

Another small study from 2019 shows that consuming one cup of kefir daily decreased fasting blood glucose, HgA1c levels and insulin resistance in patients with newly diagnosed type 2 diabetes, says Caroline Margolis, a registered dietitian with Lifeway Foods in Michigan.

Might Reduce Inflammation

Studies suggest kefir may aid in reducing inflammation by inhibiting the activity of proinflammatory cytokines—proteins that play a role in pain and inflammation—and increasing anti-inflammatory cytokine concentrations to reduce the risk of certain diseases and disease-related complications, says Margolis.

In one small study examining the effect of kefir on markers of metabolic syndrome, 62 people with metabolic syndrome consumed either 180 milliliters of kefir or unfermented milk daily for 12 weeks. Those who consumed the kefir had significantly increased apolipoprotein A1, a major component of HDL “good” cholesterol, and decreased cytokines compared to those who drank the unfermented milk.

May Improve Brain Health and Mood

“While studies indicate that kefir, along with a diet rich in fiber, may balance the microbiome to reduce the risk and symptoms of psychological disorders such as anxiety and depression, it may also have an effect on memory and cognition, and a reduced risk of neurological diseases, thanks to its ability to reduce inflammation,” says Margolis.

It’s important to include fiber when consuming probiotics as fiber is the fuel used by probiotic organisms while in the GI tract.

In one small study examining the effect of kefir on memory, adults who consumed 8 ounces of kefir daily for four weeks had significantly improved relational memory and increased concentration of Lactobacillus in the gut compared to a placebo.

Helps Build Stronger Bones

As kefir is a dairy product containing calcium, vitamin D and phosphorus, it may help build and maintain strong bones, says Maisano. A review of studies examining important nutrients for bone health found that fermented dairy products are associated with a reduced risk of hip fracture.

Helps Protect Against Viruses

Kefir’s anti-viral properties can help your immune system fight off viral infections, says Pacheco. A review of studies examining kefir’s effects on the immune system found that kefir promotes production of immune cells that can suppress viral activity.