Kimchi is a traditional Korean dish of fermented vegetables. (Getty Images)

By now you’ve probably heard that a little bacteria in your food isn’t always a bad thing. Beneficial live bacteria and yeasts, called probiotics, which are found in some foods, have been associated with many benefits: weight loss and improved digestion and immunity, among others. Some evidence suggests that probiotics may help shorten a bout of diarrhea and improve symptoms of irritable bowel syndrome. But more research is needed to support those claims and others.

Probiotic foods are made through the process of fermentation. As bacteria chemically alter the food — say, turning milk into yogurt — they secrete enzymes, organic acids and proteins. Some of the potential health perks of probiotics may be due to those compounds, says Gail Cresci of the department of gastroenterology and hepatology at the Cleveland Clinic. That’s why food is a better choice than supplements.

Benjamin Wolfe, an assistant professor of microbiology at Tufts University, says, “The benefits people get from fermented foods come largely from improved digestibility and the nutrients the foods provide.” In many cases, fermentation adds nutritional value.

To get more gut-boosting bacteria, consider incorporating these three probiotic foods into your day.


Combine sliced cabbage with kosher salt, then cover. The bacteria present on the surface of the cabbage leaves will ferment the vegetable’s natural sugars into lactic acid, creating sauerkraut. In addition to having healthy bacteria, sauerkraut is an excellent source of vitamin C. Kimchi is a similar fermented food.

Look for: Refrigerated products, such as Bubbies and Farmhouse Culture. Shelf-stable varieties are pasteurized, which kills the healthy bacteria.

Use it: To add tartness and crunch to a salad or for roasted vegetables and grains.


Yogurt is made when milk has been inoculated with friendly bacteria, usually Lactobacillus bulgaricus and Streptococcus thermophilus. The microbes alter the milk’s natural sugar, lactose. That process thickens the yogurt, producing the sour, tart flavor you expect. It also makes yogurt less likely than milk to cause bloating, gas and other digestive discomfort in lactose-intolerant people. “The microbes essentially predigest the food,” Wolfe says. “That makes it more pleasant to eat.”

Look for: Plain yogurt made with live active cultures. Sweetened yogurt can pack as many as three teaspoons of added sugars; plain has natural sugars in the form of lactose. If you prefer flavored yogurt, add fruit or look for a low-sugar option, such as Siggi’s Icelandic Style Yogurt.

Use it: Top a bowl of plain yogurt with chopped tomatoes, cucumbers, black olives and a sprinkle of the Middle Eastern herb blend za’atar.


Adding microbial cultures to cooked soybeans results in this dense, chewy cake with a nutty texture. Tempeh is higher in protein and fiber than tofu, and some say it’s easier to digest.

Look for: Shrink-wrapped packages near the tofu and meat alternatives in supermarkets. Some brands, such as Lightlife, have grains or seeds, which alter the texture and flavor.

Use it: Slice and marinate for 30 minutes in lower-sodium soy sauce (or tamari), rice-wine vinegar and sesame oil. Pan-fry until golden. Serve with stir-fried vegetables.

Prebiotics have benefits, too

What do asparagus, garlic, Jerusalem artichokes, leeks, onions and whole wheat have in common? In addition to being the makings of a tasty dish, they contain specific types of fiber that act as what are called prebiotics.

These compounds feed the healthy probiotic bacteria in your body, helping them to grow and thrive. It’s this dynamic duo that might be responsible for many of the benefits probiotics get credit for, such as improved gastrointestinal and immune health. Some manufacturers add prebiotic fibers (namely fructans, galacto-oligosaccharides and inulin) to packaged foods to boost the fiber content. But it’s better to get your prebiotic fibers from foods that naturally contain them, because they can cause digestive distress in large amounts.

Copyright 2017. Consumers Union of United States Inc.

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