Lots of talk last month about the health effects of gut bacteria at the Academy of Nutrition and Dietetics’ food and nutrition conference in Chicago. The right balance of good bugs in our lower intestines can stimulate our immune system, help manage our weight and perhaps even protect us from diseases like type 2 diabetes, according to some research.
Essential to this process is dietary fiber, we were informed by Dr. Dennis Gordon, Professor Emeritus at North Dakota State University and former research scientist at Oregon State University.
Our “microbiota” are the trillions of bacteria, viruses and funguses (fungi) that live on or in our bodies, he explained. Some are healthful “probiotics” and some are harmful, especially if they outnumber the good guys.
Good bacteria feeds on dietary fiber — the indigestible part of plant foods. Similar to a septic tank, when fiber from the diet is present in the digestive tract, microbes in the large intestine ferment it into substances that help regulate important body processes.
Therefore, fiber in our diets actually feeds the beneficial bacteria in our guts. Fiber also stimulates the intestines to do their job, says Dr. Gordon, who believes dietary fiber is vital for health. Not everyone agrees, however. Dietary fiber is not considered an essential nutrient by current dietary guidelines.
Our individual gut microbes are determined by the food we eat as well as our genetics and get this … by the amount of stress in our lives. Stress can change our microbiota and contribute to health issues, we learned.
Researchers are just beginning to understand how the multitude of microbes in our guts affect our health. And we still don’t know what probiotic mixtures are the most beneficial. That’s because every time we change our diets or our environment, our gut microbes change, too. Taking a daily probiotic supplement only changes gut microbiota one-tenth of 1 percent, says Gordon.
His advice to get the most beneficial mixture of healthful “probiotic” microbes? Eat a diverse supply of dietary fibers from a variety of plant-based foods. That includes all types of vegetables and fruits, beans, whole grains and nuts. “The science supports diversity,” he emphasized.
What about fiber supplements? They can help but all fibers collectively — from a variety of foods — are the most potent for gut health, says Gordon.
Researchers continue to untangle the fascinating world of intestinal microbes and health. For now, the best way to encourage beneficial bacteria to populate our bodies is pretty simple, says Gordon.
“Eat moderate amounts of a variety of foods, especially plant foods high in fiber. Exercise. And manage stress. That’s the formula for health.”
Barbara Quinn is a registered dietitian and certified diabetes educator affiliated with Community Hospital of the Monterey Peninsula in California. She is the author of “Quinn-Essential Nutrition” (Westbow Press, 2015). Email her at to firstname.lastname@example.org.