Probiotics are beneficial bacteria in your intestinal tract that can improve health. And probiotics can also help improve immune system function. Probiotics interact with a specific part of your small intestine called the Peyer's patches, which directly signal your immune system to be vigilant.
"Some probiotic drink mixes out there contain beneficial probiotic organisms," says Patricia David, MD, MSPH, president of Healthy U in Columbus, Ohio. "And those are great if you're on the go. But I encourage people to obtain their probiofics directly from food sources whenever possible - these food sources include yogurt, buttermilk, goat's milk, coconut water, soy milk, miso, kim chi, and sauerkraut. For optimum probiotic exposure, look for yogurts and other probiotic products that contain bifldobacterium and/or lactobacilli.
Another way to increase your levels of beneficial immune-bolstering bacteria is to consume prebiotics - nondigestible food components that selectively stimulate the growth of "good" bacteria in the gastrointestinal tract, says Dr. David. "Natural sources of prebiotics include dandelion greens, spinach, kale, artichokes, legumes, onions, leeks, garlic, oatmeal, flaxseed, barley, and soy yogurt." she says. (‘The Doctor’s Book of Food Remedies’, by Selene Yeager and the Editors of ‘Prevention’ magazine)