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It’s true: The (very) little things in life matter most. Your gut is home to trillions of helpful critters. These bacteria—called “probiotics”—are increasingly seen as essential for good health, in digestion and beyond.
Recent research trumpets the state of our guts as important for immune-system well-being, heart and mental health, and weight management. The perks may extend to athletic efforts as well. While research in this area is still emerging, there have been some promising studies. One, in the Journal of Science and Medicine in Sports, suggests probiotics can help shield athletes from upper-respiratory-tract infections, and a separate report, in the Journal of the International Society of Sports Nutrition, indicates that probiotics could lead to reduced stomach woes such as nausea, cramps and the loathed mid-run bowel distress.
The good bacteria in your gut keep the bad guys in check. But this balance can get skewed by stress, poor eating habits, antibiotic use (beneficial bacteria also get swept up in the raid) and potentially even heavy training.
Luckily, your grocery cart could hold the answer to keeping your gut bacteria properly balanced. Look for foods that have undergone fermentation, a process by which beneficial bacteria are infused either directly by humans or indirectly through natural processes. Enhance your diet with any of these six not-so-fresh foods to nurture your microbiome. Because probiotics in the gut can die off quickly, frequent eating is key.
Certain foods contain prebiotics, special fibers the probiotics in your digestive system use as a food source. Think of prebiotics as fertilizers for your gut; they help probiotics sprout in greater numbers. Dietary sources include almond skins, asparagus, sunchokes, chicory, partly green bananas, leeks, wheat bran and legumes.
With all the hoopla around probiotics, food manufacturers are adding them to energy bars, juices and protein powders, and supplement aisles are devoting space to pills, liquids and chewables with gut-friendly bacteria.
It’s OK to use these products to bolster your overall probiotic intake, alongside a daily dose of fermented foods. If turning to a supplement, look for one with multiple bacterial strains and numbering at least five billion colony forming units (CFUs), to better mimic the gut’s natural diversity.
Submerged in brine for several days, fresh cabbage slowly ferments into crunchy, tangy sauerkraut. Think of it as Western kimchi (see below). Seek out sauerkraut that has not been heat treated (sometimes labeled “raw” or “unpasteurized”) to ensure the friendly bacteria are still there for the taking.
Serving suggestion: Serve sauerkraut as a side dish, or use its quintessential bite to enliven grains, salads, pork chops, burgers, sandwiches and pizza.
Like yogurt, kefir is a fermented dairy product. But compared to its counterpart, this drinkable product contains a larger and more diverse population of bacteria—an important fact, as researchers have yet to nail down precisely which strains provide the greatest health benefits. Opt for plain to sidestep the sugar deluge of flavored versions.
Serving suggestion: Use as a base for your post-run smoothies, pour over granola or use in place of buttermilk in recipes like pancakes.
Thanks to the food-truck craze, kimchi is no longer an obscure food. This traditional Korean condiment is made by mixing vegetables (most often cabbage) with a fiery garlic-chili seasoning and letting lactic-acid bacteria go to work. Kimchi is a way to get your salty, sweet, sour and spicy fixes all at once.
Serving suggestion: Kimchi’s heat goes well with everything from tacos to scrambled eggs to soups to sandwiches to burgers.
While this fizzy, fermented tea is no stranger to hipsters and the yogi clan, kombucha can also give runners a big probiotic bang for their buck. Each sip is thought to contain several different strains of bacteria. On a sour note, a lot of the kombucha on the market also delivers hefty amounts of sugar. Shop around for varieties that contain less of the sweet stuff.
Combine cooked soybeans with salt, koji (an enzyme that breaks down proteins) and rice or barley, and then leave it to ferment for several weeks, and you end up with an umami bomb with a nut-butter consistency. Miso can be salty, but that’s a boon if you regularly sweat up a storm. To keep the bacteria in miso alive, don’t expose it to high heats by, for instance, whisking it into boiling water for a soup.
Serving suggestion: Blend into salad dressings, whisk with warm water and rehydrated dried seaweed for post-run nourishment, stir into mashed potatoes or mix with rice vinegar and sesame oil and brush over cooked fish.
Now a health-food staple, tempeh is made by fermenting cooked soybeans into a firm, chewy patty. Beyond its helpful bacteria, nutty-tasting tempeh is a complete, vegetarian protein to show your muscles some love.
Serving suggestion: Crumble up and add to chili, stir-fry, tacos, soups, casseroles, steamed veggies and pasta sauce, or grill it like a burger.
This article originally appeared in our September 2016 issue.