Cold potatoes—that is, taters that have been washed, cooked, and cooled—are one of the best sources of resistant starch. Resistant starch is a prebiotic, a type of indigestible carbohydrate that acts like food for gut bacteria, encouraging the good bugs to grow and flourish. While resistant starch has many health benefits, one of its most promising aspects is its ability to increase insulin sensitivity, helping people reduce diabetes risk and even lose weight. Find out everything you need to know about probiotics before you start taking them.
Think of kefir as yogurt’s tangier but more powerful cousin. The drink is made by seeding milk with kefir “grains,” which are tiny bundles of yeast and bacteria, and letting it sit. Over time the grains ferment the milk, producing a tart drink full of healthy bacteria for your gut, which makes it one of the best probiotic foods you can eat! A 2013 study found that kefir can help relieve gastrointestinal problems and allergies and may even have a positive effect on heart health. One caveat, however: Many commercial kefir drinks contain very high amounts of added sugar, which feeds bad bacteria in your gut, so make sure you read the label and ingredient list.
Most people go out of their way to avoid green bananas, but there’s good news for people who just can’t wait until they’re fully ripe. Green bananas are a rich source of prebiotics, particularly resistant starch. They also have a healthy dose of both soluble and insoluble fiber, vitamins, and minerals. The combo provides a feast for good gut bacteria and helps protect your heart and bones. Can’t get past the taste? Try them boiled or fried or sub some green banana flour in place of regular flour. Watch out for these clear signs your gut health needs a boost.