Puzzled by probiotics? You’re not alone. Scientists are just beginning to unlock why and how probiotics, the “good” bacteria that live in your gut and aid digestion, can boost your health. Research suggests they are responsible for a variety of benefits including supporting the immune system, relieving depression and helping to prevent obesity. You’ve probably seen probiotics in capsule or powder form, but you can also find this friendly bacteria in many foods you might already be eating.
“Food has an almost immediate effect on your intestinal environment, which is composed of trillions of microbes.”
“There is no science out there that I am aware of regarding which is a better delivery method: supplements or food,” says Kristi King, R.D., spokesperson for the Academy of Nutrition and Dietetics. She warns that probiotic supplements are not regulated by the FDA, meaning what’s on the label might not necessarily be what’s inside. “Someone whose immunity is compromised should be especially cautious about taking a supplement that isn’t regulated by the FDA.”
Here’s what researchers do know: Food has an almost immediate effect on your intestinal environment, which is composed of trillions of microbes. “You can replenish your bacteria flora within three to four days,” says Gina Sam, MD, MPH, Director of the Mount Sinai Gastrointestinal Motility Center at The Mount Sinai Hospital.
But the jury’s still out concerning how often — and in what quantities — you’d need to consume certain probiotics to reap the benefits. “It’s frustrating for me as a health care provider, because people want a solid answer but the research just isn’t there quite yet,” King says. She notes that though there are hundreds and hundreds of strands of probiotics, only the two most common strands, Lactobacillus and Bifidobacterium, have been widely studied.
Since probiotic dietary supplements lack strong scientific evidence demonstrating their safety and effectiveness, your best bet may be adopting a probiotics-rich diet. (Plus, supplements can be pricey!) And remember, if you have persistent gastrointestinal distress, you should always consult a physician.
9 Foods With Probiotics
1. Yogurt
Did you know there are tens of billions of bacteria per serving of yogurt? When making this dairy-aisle favorite, producers add cultures of bacteria after milk has been pasteurized, to ensure the bacteria survives. “Some brands have more live and active cultures so people have to be aware of reading the labels,” says Dr. Sam. Be on the lookout for the National Yogurt Association’s “Live & Active Cultures” seal, which certifies that the product contains at least 100 million cultures per gram, or 20 billion per eight-ounce serving.
2. Kefir
A milky beverage originating in Russia and Turkey, kefir is thought to be an even better source of probiotics than yogurt. Made by fermenting goat, cow or sheep’s milk with kefir “grains,” this drink contains ten to 20 different types of bacteria. According to research published in the American Journal of Dietetics, kefir has been proven to help ease lactose intolerance in some adults. Don’t like the tangy taste? Try using kefir instead of milk in your favorite smoothie recipe.
3. Kimchi
Spicy and sour, this traditional Korean side dish is made by fermenting cabbage, cucumber or radish. Since it’s mostly pickled vegetables, kimchi is a great low-calorie source of fiber. When making sandwiches, stir-fries or soup with this unique ingredient, just be sure to add it last to avoid cooking off the good bacteria. Early research demonstrates a link between kimchi consumption and immune system regulation.
4. Sour Pickles
Salty pickle spears also deliver a punch of probiotics. Seek out varieties that are brined in water and sea salt instead of vinegar, says Dr. Sam. Vinegar brine won’t allow the beneficial bacteria to grow. Bonus: Pickle juice is rich in electrolytes, and has been shown to help relieve exercise-induced muscle cramps.
5. Kombucha
Come-boo-what? Kombucha (pronounced cum-bu-cha) is a slightly sweet and fizzy liquid that results when sweet black tea is fermented with a mushroom-like colony of bacteria called a “scoby.” King recommends kombucha as a potent source of probiotics — provided they’re clearly marked on the label. Each bottle of the Synergy Drink brand of fermented teas, for instance, packs one billion bacillus coagulans and one billion saccharomyces boulardii, two types of organisms that are thought to help and prevent diarrhea. However, because cultures and preparation methods will differ, it’s difficult to pin down exactly what probiotics will be in a given batch of kombucha.
6. Sauerkraut
Used to top sausages or as a side dish, this condiment is made from fermented cabbage. Keep in mind, not all supermarket sauerkrauts will have beneficial bacteria. Dr. Sam says to check if the sauerkraut has been pasteurized because this process will destroy probiotics. Just remember: Always consult a physician before eating unpasteurized foods while pregnant.
7. Sourdough Bread
Probiotics in bread? Believe it. This tangy toast is made with sourdough starter (which functions like yeast) and contains lactobacillus. Since sourdough is low on the glycemic-index, it will keep you full for longer instead of igniting a short-lived energy spike and crash.
8. Miso
Soybeans fermented with brown rice produce miso paste, a popular seasoning used in Asian cuisine. The fermentation process is what makes this condiment a source of lactobacillus acidophilus. Since it has a strong, salty flavor and lots of sodium, a little will go a long way! Dr. Sam notes that there are reported to be over 160 strains of probiotics in miso.
9. Tempeh
Another food formed from fermented soybeans, tempeh is a firm, white block that’s frequently used as a protein-packed meat substitute for vegans and vegetarians. Keep in mind, it has more calories — but more protein, fiber and probiotic potential — than tofu, which is also soy-based.
Powered by Probiotics
If you’re experiencing gastrointestinal distress or want to boost your immunity, any of these natural sources of probiotics could provide some relief. “Not only do these probiotic-rich foods give us good bacteria, but most of the foods will give us other health benefits as well,” says King. “It’s a win-win situation.”
Consumers have a wide variety of capsules, liquids and foods to choose from, so it’s important you choose the option that fits with your budget, taste preferences and wellness needs. Still unsure? Talk with your physician to discuss if a medical grade probiotics prescription could be right for you, King says.
Originally posted August 2014. Updated April 2015.