About 70 percent of your body’s immune cells live in your gut. Therefore, it’s important to keep your gut in good shape. Probiotics have been known to benefit the gut microbiota. They are often called “good” bacteria. There are different forms of probiotics. Good sources of probiotics include yogurt, sauerkraut, tempeh, miso, kombucha and kimchi. Prebiotics are fibers which also support gut health and are found in onions, leeks, radishes, carrots, bananas, asparagus, flax and chia seeds.