We love how probiotics keep our gut healthy and boost our immune system. But did you know you can increase their effectiveness by adding prebiotic foods to your diet, or combining them both in a synbiotic? Here’s why they should both be part of your healthy eating routine.

Probiotics are beneficial live bacteria.
Our gut is full of good bacteria that help move food effectively through our digestive tract and keep inflammatory digestive ailments like irritable bowel syndrome and diarrhea at bay. These bacteria keep our immune system intact, too; a whopping 80 percent of our immune function originates in our gut.

Probiotic-rich foods and probiotic supplements contain live cultures of good bacteria, most often strains of lactobacillus, S. cerevisiae and Bifidobacterium, that help our internal bacteria work better. A good dietary source of probiotics? Fermented and cultured foods like yogurt (with live cultures), unpasteurized sauerkraut (not in vinegar, this kills the bacteria), miso soup, kombucha, fermented soft cheeses, kefir, buttermilk or tempeh. (Read more about the benefits of fermented foods.)

Supplements are another easy way to get high-potency probiotics, says Cordelia Apple, nutritionist at our Portland store. Garden of Life Raw Probiotics Ultimate Care, made from whole food probiotics, is one of her favorites; for kids, try Garden of Life Dr. Formulated Organic Kids+ Probiotic Chewables with added vitamin C and D.

Prebiotics feed our good bacteria.
Consuming probiotic-rich foods or supplements isn’t the only way to boost the beneficial strains of bacteria in our gut—we can also consume certain non-digestible foods that feed the bacteria, called prebiotics. (Another benefit? Studies show that prebiotics can increase absorption of calcium and improve bone mineral density.)

Prebiotics come from foods that are rich with inulin and resistant starches. You can find these helpful fibers in bananas, garlic, honey, maple syrup, asparagus, Jerusalem artichokes and chicory root. Fiber supplements that feature acacia fiber are especially good prebiotics, says Cordelia. Try Renew Life Skinny Gut 100% Organic Acacia Fiber or Garden of Life Dr. Formulated Organic Fiber.

Synbiotics combine prebiotics and probiotics.
We can amp up the benefits of prebiotics and probiotics by taking them together, creating a synergy called synbiotics. Blending a prebiotic like honey with a probiotic like yogurt or kefir gives us a powerful synbiotic.   Or mix some acacia fiber powder with yogurt in a smoothie. Sour pickled asparagus meets the synbiotic criteria, if you pickle it without vinegar (try this vinegar-free recipe for sour pickles). And of course, supplements are a simple way to get synbiotic benefits; try a daily dose of Jarro Formulas Jarro-Dophilus +FOS capsules.

Keep your healthy bacteria thriving.
A diet that includes prebiotics and probiotics or combined synbiotics keeps our digestive and immune systems on track, but there a few other ways to be sure we stay in sync. For optimal gut functioning, limit antibiotic use when you can, since these drugs kill off both the good and bad bacteria in our bodies. Limiting sugar and fat in your diet is also important, as scientists have shown that these disrupt our good gut bacteria. Stress can destroy beneficial bacteria too, say researchers, and lower our immune system’s effectiveness.