The good news keeps stacking up for probiotics, the good-for-you bacteria that keep your GI system functioning in tip-top shape. "Research is finding that a healthy microbiome may play a role in reducing inflammation, a risk factor involved in illnesses ranging from colds to cancer, heart disease, arthritis, and cognitive decline," says Katherine Tallmadge, RD, author of Diet Simple. In addition, the bacteria may help burn body fat and reduce insulin resistance, she says. So to stay slim and healthy, consider adding more probiotic foods to your diet, like the ones that follow.
We have to give a nod to the most famous probiotic food: yogurt. Whether you love Greek or regular, low-fat or full-fat, look for the phrase "live active cultures" on the label. And although choosing a plain yogurt has less added sugar than the flavored kinds, Tallmadge gives you the okay to choose a fruit-infused flavor if that's the only way you'll eat it. Just be sure to aim for fewer than 15 grams of the sweet stuff per serving; sugar can feed the bad bugs in your gut.
This smooth, slightly tangy, and sippable yogurt contains a dozen different types of live active cultures. It's also 99% lactose-free, making it easier to digest for those with intolerant tummies. "If you have lactose intolerance, start slowly on kefir as a test. If you have no symptoms, go ahead and slowly increase your intake," advises Tallmadge. Plus, with 8 to 11 grams of protein per cup (depending on the brand), it can help fill you up for around 100 calories.
Made from aged, fermented soybeans, this paste is brimming with probiotics. You can buy miso paste in a bunch of varieties (white, yellow, red, brown) and the darker the color, the deeper the taste. Miso is a great way to add a burst of earthy, savory flavor for few calories (only 25 to 30 per tablespoon), plus protein, fiber, and bone-strengthening vitamin K, says Sharon Palmer, RDN, author of Plant-Powered for Life. "While we need more research about how these types of fermented foods contribute to health, it's a good idea to introduce more of them into your diet," she says. Use miso to glaze fish or chicken before cooking, mix into a stir-fry recipe, or add to liquid to make a miso broth. One caveat: Miso is very high in sodium. One teaspoon, enough to make a cup of miso soup, has 473 mg of sodium, 21% of the daily recommended limit and 32% of the daily limit for those with high blood pressure.
Fizzy, tangy, and even slightly vinegar-esque, kombucha has a cult following for a reason. The tea gets its natural carbonation from the "scoby" (that float-y thing you see in some bottled varieties), which is actually the bacteria and yeast that ferment the drink and creates the probiotics. "There's not much scientific evidence specifically on the benefits of kombucha, but it is another strategy to introduce more live, active bacteria into your lifestyle," says Palmer. Many are made with fruit juice for added flavor, so read the label to see what you're getting, she advises. Stick to store-bought kombucha; it's tough to keep the tea sanitary when you make it yourself, and homebrewed kombucha been linked to nausea and even toxicity. Also note that due to the fermentation process, kombucha contains trace amounts of alcohol, so it's best to stick to one 12-ounce bottle a day.
This cabbage condiment can frequently be found atop a mighty hot dog, but its roots trace all the way back to the 4th century B.C. Cabbage was fermented to preserve the veggie, resulting in what we all know as sauerkraut. Palmer points out that modern techniques for canning sauerkraut results in a product packed in a vinegar solution without live, active bacteria in the mix. For most probiotic power, eat fresh sauerkraut (look for live cultures on the label or buy it in the refrigerated section) or make it yourself at home.
This mildly sour, chewy bread is made with a lactic acid starter that contains strains of lactobacillus, a friendly type of bacteria that adds good microbes into the bakery staple. Sourdough may be the healthiest bread choice if diabetes is a concern for you: one 2008 study found that people with pre-diabetes who ate sourdough bread had less of a blood sugar spike compared to when they ate bread made with baker's yeast. (Experts also say fiber-rich whole grain bread can also reduce a post-meal blood sugar spike.) The researchers credit the lactic acid for the favorable effect.
Tempeh is made with fermented soybeans or grains that have been molded into a cake-like form. The nuttier, tangier cousin to tofu can be sliced for sandwiches, tossed into stir-fries, or marinated and grilled. In addition to probiotics, tempeh contains about 15 grams of protein per half-cup and is a good source of iron. Plus, soy foods contain compounds that may help keep cholesterol in check, according to a study in The American Journal of Clinical Nutrition. Palmer likes to use tempeh in place of tofu in dishes like stir-fries, salads, and side dishes.