By Dr. Nora DeVoe, Ph.D.
Geriatric Care Manager



Microbes are bacteria and other tiny critters not visible to the naked eye but numbering in the trillions and busy in your body. Many of these microbes benefit you. Others have the potential to cause harm. This community of microbes is called the microbiota. Their genes are called the microbiome.

In recent years, we have realized our microbiota performs functions either directly or indirectly that could impact the functioning of our body. For example, scientists are exploring how the microbiota may be involved in the maturation of the immune system, energy metabolism, and how our brain functions. That is not all. Disruption of the normal human gut microbiota has been associated with many different health conditions such as asthma, allergies, irritable bowel syndrome, obesity, type 2 diabetes, cardiovascular disease, and colorectal cancer, among others. Exactly what role the microbiota might play in these conditions is uncertain.

Your microbiota makes up about three pounds of your body weight. That is what your brain weighs. Microbes are found on your skin and in just about every part of your body, such as your mouth, nose, and eyes. But the vast majority of microbes are in your gut, particularly the large intestine.

Many factors impact the makeup of your microbiota, such as your genetics, age, sex, disease conditions, where you live, and medications such as antibiotics. A potentially big influence on your gut microbiota under your control is what you eat regularly. Eating probiotic rich foods like yogurt with good bacteria may be the first way that comes to mind for shaping the makeup of your gut microbiota. What some people do not realize is that probiotics are not one size fits all. Research shows that certain benefits associated with probiotics, such as supporting immunity or easing constipation, are specific to the species and strain of bacteria. Fermented foods like yogurt typically only contain a few different bacteria, while our gut is estimated to contain about 1,000 different species.

Another way to influence your gut microbiota is by changing what you feed the bacteria. In recent years, scientists have been looking more closely at how what we eat influences which microbes thrive in our body. There are several components of our diet classified as prebiotics that influence the growth of the microbiota or the products they produce. Certain dietary fibers that are fermented by intestinal bacteria but not digestible by people are the main type of prebiotic recognized by scientists. There are other components of food that may also impact the microbiota. There is some evidence that certain lipids or fats could impact the diversity and type of microbes that exist in our gut. We are just really starting to learn about all of the different dietary components that could influence the gut bacteria. In general, the greater the diversity of bacteria in your gut, the better off your health may be. A loss of diversity of the gut microbiota has been found in several disease conditions such as obesity, type 2 diabetes, inflammatory bowel diseases, etc.

The diversity of the microbiota of individuals consuming a typical western diet low in fiber and high in processed foods is generally less than in people in other parts of the world. To nourish your microbiota, try to eat more fruits, vegetables, whole grains, legumes, and nuts. Really eat the rainbow; make sure you are ingesting a variety of colorful plant foods. Make healthy eating a habit. What you eat day in and day out is what impacts your microbiota most. Eat a wide variety of plant foods and challenge yourself to try fruits and vegetables you have never eaten. Choose whole grains instead of refined grains. The higher fiber content of whole grains supports your gut bacteria. Enjoy yogurt and kefir (fermented milk) and choose the ones that note live and active cultures.

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Nora DeVoe is a Gerontologist specializing in Eldercare and Caregiver issues. She may be reached at (716) 667-7299.  

Dr. Nora is a ....