The good bacteria that probiotics provide can't thrive in our guts alone. Prebiotics—which include soluble fibers—support probiotics and offer their own potential health benefits as well.
Our secret shopper visited a natural products store in the Mountain West to see what one employee knew about prebiotics.
Natural Foods Merchandiser: Do I need prebiotics more than probiotics, and how do I find them?
Retailer: Both are important for good digestion, which is so important for immunity, sleep, you name it. So I’d say to try to get both, whether from food or supplements. We have all kinds of prebiotic and probiotic supplements and some that include both.
NFM: Great. So one is not necessarily more important than the other?
Retailer: That kind of depends on how healthy your gut is now. If you’re having digestive issues like loose stools or bloating, a probiotic should help. If you’re just looking to keep everything working well, maybe go with a prebiotic.
How did this retailer do?
Our expert educator: Nicole Avena, Ph.D., research neuroscientist and nutrition expert at Mount Sinai School of Medicine
Overall, I think this retailer did a great job! The only place I would say she could’ve done better would be to have given more in-depth answers and provided examples, but she got the basics correct.
Probiotics are actual live strains of bacteria that can be ingested to supplement a gut that is deficient in good bacteria. The retailer was right in that they are available in supplements and in certain foods. Probiotic foods are usually fermented in some way so that they contain living strains of bacteria. These include miso soup, kimchi, kombucha and kefir.
As for prebiotics, they are fibers from specific plant foods that the bacteria in our gut feed on so that they can proliferate and keep us healthy. Foods that contain prebiotics include bananas, onion, garlic, oats, beans and apple skins—AKA foods that are high in fiber.
As for when we should consume prebiotics or probiotics, as the retailer implied, probiotics are usually only needed if the gut microbiota is deficient in some way—not as diverse as it should be. Prebiotics, on the other hand, are simply part of a healthy diet since they are often found in fruits, vegetables and whole grains. Prebiotics can also be more effective at doing their job, since they aren’t living like probiotics are. Probiotics sometimes have difficulty surviving past the stomach and don’t end up staying in the body for any significant amount of time.