All About Probiotics

Everyone from registered dietitians to primary care physicians have long understood that a healthy and varied diet comes with major health benefits. We are just now beginning to understand exactly how some of the long-hidden components of good nutrition work. One of those components doing lots of good work behind the scenes is beneficial gut bacteria. This article is all about what they are, what they do, and how you can get more and keep them happy.

What is a probiotic? Probiotics are foods that contain beneficial bacteria. That’s right. We are used to thinking of bacteria as an enemy of good health, but there are lots of “good guy” bacteria, too. About 1,000 different kinds, all living in your gut. Probiotics come in many delicious and healthy foods, including yogurt and just about anything that’s fermented. Think kimchi, kombucha tea, raw apple cider vinegar, both dairy and nondairy kefir, and fermented pickles. You eat the healthy bacteria, and they go on to live and reproduce in your gut.

What can they do? A healthy number of healthy bacteria can provide numerous benefits and perform important functions in the body. First of all, they protect your digestive tract from harmful bacteria and fungi. Beyond that, though, they have been identified in many of the body’s crucial processes, including those related to metabolism and immune response. They help break down and digest food, decrease inflammation, and may help moderate insulin response. Some recent research has even linked the consumption of probiotics to improved anxiety and depression and reduced risk of colon cancer.

Researchers have also found that beneficial bacteria produce vitamins (thiamine, riboflavin, vitamin B12, and vitamin K), enhance absorption of some minerals, help regulate weight, and improve heart health.

It seems pretty easy, right? Add some probiotics to your diet, and you get all of these spectacular health benefits. But it isn’t quite that simple. Probiotics are organisms, just like you. They need to eat too. And good bacteria are particular. They like “prebiotics.” Prebiotics contain a type of fiber found in vegetables, fruits, and legumes. Foods especially high in prebiotics include beans and peas, oats, bananas, berries, asparagus, and garlic, leeks, and onions. Each contains high amounts of fiber that humans cannot digest. The fiber goes on to feed the gut bacteria.

So what do probiotics do with prebiotics? One of the amazing things probiotics can do with enough of their own healthy prebiotic food is make a short-chain fatty acid called butyrate, which provides colon cells with about 70% of their total energy needs. Early research points to the high likelihood that butyric acid may help alleviate irritable bowel syndrome and Crohn’s disease and could help prevent and treat colon cancer.

Can I get these things in pill form? Lots of companies have sprung into action offering supplements that claim to offer the benefits of ingesting pro- and prebiotics. Supplements are often poorly regulated and unproven. It is almost always better to get your nutrition from the actual foods, rather than supplements. Be careful, though. It is possible to eat too many pro- and prebiotics. Talk to your doctor or a registered dietitian about how to incorporate these important nutrients into your diet.

What about antibiotics? While the use of antibiotics may be necessary to treat some diseases, they can be harmful to both the pathogen you are trying to fight and all of the good bacteria in your gut. Use them exactly as directed by your physician in order to get the greatest benefit and the least possible harm.

By eating a varied diet with plenty of fiber, plant foods, and fermented foods you will be providing your body with a whole community of “do-gooders” along with everything they need to thrive. And that could lead to some impressive health benefits for you.  

Kristin Irace, RD, is a registered dietitian at Southwestern Vermont Medical Center in Bennington.