Staying Healthy
Do fermented foods live up to the hype?
Stores are bursting with fermented products containing probiotics. Here’s how they can boost health — and ways they may fall short.
Wander down a supermarket’s refrigerated aisle nowadays and you’ll notice shelves packed with fermented foods and drinks. Newer additions such as milk-based kefir, kimchi (Korean cabbage), kombucha (tea), and tempeh (soybeans) have joined perennial favorites such as yogurt, sauerkraut, and beer, highlighting a market projected to grow globally by $533 million over the next four years.
But the fresh popularity of fermented foods belies a heritage dating thousands of years. Ancient civilizations used fermentation, which incorporates bacteria and yeast to break down sugars and carbohydrates, to transform flavors, and prevent spoilage. Scientists have long since learned that fermented foods also contain live microorganisms called probiotics, which bolster a healthier mix of the trillions of "good" bacteria that live in our gut.
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About the Author

Maureen Salamon, Executive Editor, Harvard Women's Health Watch
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