Can Probiotics Really Help Your Health?

By: Laurie S. Herr

Probiotics are living microorganisms found in fermented foods like yogurt, kimchi and kefir. How important are they, and what are their known health benefits? We look at the science.

Homemade Kimchi

You've probably heard plenty by now about probiotics—those live microorganisms found in fermented foods like yogurt, sauerkraut, kimchi and apple-cider vinegar. Many food and supplement companies claim they can do everything from fix bad skin to fight cancer. Just how good are they for you, anyway, and do you really need them? Read on for five research-backed benefits.

Pictured Recipe: Homemade Kimchi

1. Balances Friendly Gut Bacteria

Grilled Salmon with Watercress Salad

Pictured Recipe: Grilled Salmon with Watercress Salad & Buttermilk Dressing

Back in high school biology class, you may have thought of all bacteria as bad—microscopic bugs that make us sick. The truth is, our bodies are teeming with both good and bad bacteria. In a healthy gut, the good bacteria outnumber the bad. Illness, a poor diet or taking certain medicines can throw that balance out of whack. Probiotics help out in the fight, boosting the number of friendly bacteria, improving digestion and helping our bodies absorb more nutrients.

Related: 7 Must-Eat Fermented Foods for a Healthy Gut

2. Prevents and Treats Diarrhea

Multiple studies show probiotics can help with diarrhea, especially in children. An analysis of more than 60 studies involving more than 8,000 people (mostly children) found that those who were given probiotics—either in yogurt or supplement form—got over their diarrhea symptoms an average of one day faster than those who didn't take probiotics.

Got the opposite problem? Some studies suggest probiotics may help with constipation, too. More research is needed, experts say. Still, eating more probiotic foods probably won't hurt—and they may help get you going.

3. Boosts Immunity

Korean Turkey Burgers with Kimchi

Pictured Recipe: Korean Turkey Burgers with Kimchi

Turns out there may be some truth to the old saying, "Feed a cold and starve a fever." A number of studies suggest eating probiotic foods may help strengthen the immune system, making us less susceptible to colds and other infections. In one small study, New Zealand athletes who had probiotics for four months had about 40 percent fewer colds and stomach bugs than those on a placebo.

4. May Help Ease Skin Problems

More research is needed, but evidence suggests probiotics may help with certain skin conditions like eczema. In one study, babies with eczema who were given probiotic-supplemented milk had improved symptoms compared to babies on plain milk. In another study, babies whose mothers took probiotics during pregnancy had a much lower risk of developing eczema early in life.

Other early research suggests probiotics may help treat acne, rosacea and sun damage. Experts say probiotics' ability to ease inflammation, hydrate skin and fight infection all play a role.

5. Improves Heart Health

Miso Soup Cup of Noodles with Shrimp

Pictured Recipe: Miso Soup Cup of Noodles with Shrimp & Green Tea Soba

Eating more kraut and kimchi can help your heart in a number of ways. Regularly eating probiotic-rich foods may slightly reduce blood pressure, according to the American Heart Association. Certain strains of probiotics also help lower "bad" LDL cholesterol, reducing the risk of heart disease. Some research suggests probiotics may help raise "good" HDL cholesterol as well.

The Bottom Line

Can you live without probiotics? Probably. But growing research shows that what's good for your gut is also good for your heart, skin, immunity and overall health. The science is sketchier, though, on which probiotic strains are most helpful, and experts stress that more research is needed. To be safe, stick to a healthy diet and eat a variety of foods every day. Your overall gut health also depends on eating fiber-rich and prebiotic foods, plus limiting certain foods, like red meat and processed foods. Most people can get the probiotics they need by eating fermented foods, so talk with your doctor first before you try supplements.

Watch: How to Make Kimchi

Related:
3 Surprising Reasons Your Gut Health Matters
Top Fiber-Rich Foods for Good Gut Bacteria
3-Day Meal Plan to Help You Poop

Original reporting by Joyce Hendley, M.S.