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From a young age, we are often taught to be wary of bugs as devious little things that bring harm and traumatic nightmares. But now science is increasingly showing that embracing certain critters — probiotics — is one of the best things we can do to build up a healthy body.
Inside each and every one of us a battle of the bugs is taking place at this very moment. “Our guts are populated by roughly 100 trillion microorganisms,” says Shekhar Challa, M.D., a board-certified gastroenterologist and author of Probiotics for Dummies. “About 90 trillion of those bacteria are considered beneficial to health, while the remaining 10 trillion are potentially harmful.” He goes on to explain that as long as we maintain the population of the good guys, which are commonly referred to as “probiotics,” they will keep the nefarious bacteria in check.
Probiotics including Lactobacillus and Bifidobacterium have long been praised for their powers to improve digestive health, including reducing gastrointestinal complaints such as cramping and nausea in athletes, but now science is finding that the benefits of these good-for-you critters goes beyond the gut. For starters, a robust population of probiotics in your intestines is vital to maintaining a healthy immune system. Why? “Eighty to 90 percent of our immunity is controlled by the digestive system, so if you improve digestive health with probiotics, you will automatically improve your immune health,” Challa says. Case in point: A recent study published in Nutrition Journal discovered that higher intakes of these superbugs can reduce upper-respiratory-tract symptoms in athletes. “Periods of intense training may cause a fall in immunity, setting you up for viral and bacterial infection, but probiotics can help prevent a compromised immune system brought on by the stress of training,” Challa explains.
Challa believes that weight loss is likely the next frontier in probiotic research. This stems from preliminary data showing that obese individuals have a different profile of gut bacteria than lean individuals do. Though much more human research is needed, it’s plausible that populating the zoo in our guts with elevated numbers of certain strains of probiotics could help in the battle of the bulge. Scientists at the Washington School of Medicine in St. Louis found that when certain probiotics were consumed by volunteers, the organisms altered carbohydrate metabolism in their host, which may positively impact fat loss.
Research is piling up that probiotics also can help shave down cholesterol numbers, fend off yeast and bladder infections, reduce the risk of certain cancers, improve oral health and lessen symptoms associated with anxiety and depression, which suggests there is a gut-brain connection. Probiotics are also thought to improve overall nutrient absorption, which could help improve fitness gains.
In addition to being affected by intense training, the body’s population of helpful gut bugs can be compromised by life stress, periods of poor eating, age, digestive illnesses and antibiotic use, Challa says. The latter may include exposure to antibiotic residues used in industrial meat production. The good news is that what you place in your grocery cart can go a long way toward keeping your digestive tract saturated with probiotics.
Long before refrigerators became the norm, fermentation was used as a method of food preservation. “During fermentation, microorganisms produce preservative acids in foods like cabbage and milk, which greatly increases the items’ shelf life by creating an environment in which pathogens cannot grow,” Challa says. “In doing so, the fermented food plays host to an array of probiotics that can in turn benefit your gut flora once consumed.” Here are seven foods to help you micromanage your diet.
When milk is fermented by lactic-acid bacteria, the result is tangy yogurt, probably the most common fermented food in American households. A recent study published in the Journal of Functional Foods discovered that participants who ate yogurt laced with Lactobacillus probiotics daily for six weeks shed 3 to 4 percent more body fat than subjects who did not eat the yogurt. The positive shift in gut bacteria prompted by probiotics in yogurt may favor fat burning over fat storage. Look for brands of yogurt that contain the Live and Active Cultures label, a guarantee by the National Yogurt Association that the yogurt contains at least 100 million colony-forming units of beneficial bacteria per gram at the time of manufacture. This will help you avoid buying yogurt that has been heat-pasteurized, a process that kills the fauna. Made by straining away liquid, Greek yogurt is a great way to get your fill of bugs and a payload of muscle-building protein.
Kefir is made by fermenting milk with a symbiotic colony of bacteria and yeast called “grains,” resulting in a dairy product with a notable tart flavor. Originally from Eastern Europe, kefir generally reigns supreme over yogurt when it comes to bacterial firepower, in that it harbors roughly three to four times as many probiotics (about 40 million critters per half cup). What’s more, because kefir’s live cultures break down a chunk of the lactose present in milk, some people with lactose intolerance can consume it without stomach woes. While kefir is sometimes sold in tubs with a consistency similar to yogurt, it is most often available in supermarkets as an effervescent beverage. Enjoy it by the glassful, pour it on your cereal, whisk into pancake batter in place of buttermilk or make it a powerful addition to postworkout protein shakes. Try using thicker yogurt-style kefir in dips and salad dressings. Ideally, opt for plain kefir (and yogurt!) to sidestep the avalanche of sugary calories added to flavored versions.
A staple in Japanese cuisine, this fermented paste is made by combining cooked soybeans with rice or barley, salt and koji (a starter enzyme that breaks down proteins). Traditionally, the mixture is then left to ferment for six months to three years. Miso comes in three varieties: white, yellow and red. White and yellow miso are milder in flavor, and just a touch can crank up the umami in salad dressings, mashed potatoes, brothy soups and dips. Red miso, which benefits from a longer fermentation process, has a more robust and saltier flavor, so try it in heartier dishes like stews or as a topping for roasted root vegetables. To keep the probiotics more active when making soups with miso, remove a small amount of the warm liquid and whisk the miso into it. You can then add the miso liquid back to the pan at the end of cooking. Also, be sure to purchase miso that is unpasteurized for the biggest bacterial bang for your buck.
From food trucks to restaurants owned by rock-star chefs, kimchee is everywhere these days. Borne from the need to preserve perishable foods to last through Korea’s harsh winter months, kimchee is made by fermenting vegetables (most often napa cabbage) with a fiery garlic-chili seasoning that ranges from mild to “have mercy.” A 2013 study in the journal Annals of Nutrition & Metabolism found that regularly noshing on kimchee can help trim the waistline and improve blood-sugar control. As a result of its burgeoning popularity, chefs and home cooks are now making kimchee with everything from Brussels sprouts to cucumbers to turnips. The salty, sweet, sour and spicy concoction is a powerful addition to tacos, scrambled eggs, burgers, braised greens, grilled cheese, pizza, stews, stir-fries, soups and rice dishes. Once only found in Korean markets, kimchee can now be purchased in many natural food stores and even in some larger supermarkets.
Think of it as a Western version of kimchee. Submerged in salty brine for several days, cabbage slowly ferments with the help of bacteria such as Lactobacillus into the crunchy, sour condiment we know as sauerkraut. Sauerkraut is often the first DIY fermentation project home fermenters undertake because it requires very little skill and equipment beyond a large jar, salt and a nice head of cabbage. Great as a stand-alone side dish, sauerkraut also can instantly jazz up sandwiches, mashed potatoes, coleslaw, tacos, enchiladas, scrambled eggs, grain salads, burgers and nearly anything made with pork. When purchasing sauerkraut from stores or farmer’s markets, be sure to select only brands that have not been pasteurized because the heat process used in some commercial brands (which makes it able to be sold without the need for refrigeration) will lay waste to the beneficial bacteria.
Whether you’re a vegetarian or not, it might be time to toss a package of meaty tempeh into your shopping cart. Unlike tofu, which is made from unfermented soymilk, tempeh is a patty originating from Indonesia that’s made from a base of fermented soybeans. Beyond its payload of probiotics, tempeh also has higher protein, vitamin B-12 and fiber levels than tofu. Its flavor can be described as smoky, nutty and earthy in a mushroom kind of way. Slabs of tempeh can be marinated and grilled like you would steak or chicken. Also, try crumbling it up and adding it to chili, stir-fries, tacos, soups, casseroles or pasta sauce. Unlike other fermented foods, tempeh should be cooked to rid it of undesirable microorganisms.
Though it has been sipped in areas of China for more than 2,000 years, this tea-based fermented beverage has only recently become a trendy healing elixir among the Hollywood and yogi clans. Kombucha is made by combining tea with a mother starter and a bustling colony of bacteria and yeast. The tea is then left to do its fermentation thing for a week or more. The shorter the fermentation period, the sweeter the beverage will be. Longer fermentation periods result in a drink that is lip-puckeringly vinegary with a higher alcohol content. Some swear that drinking small amounts during the day can improve energy levels and digestion. Kombucha can make for an interesting marinade or brine for meats — or try it in salad dressings. When kombucha is bottled, it’s often heavily sweetened by manufacturers to make it more palatable, so compare brands and look for those with the least amount of added sweetener.