What the Heck is the Microbiome and Why Should I Care?

Have you ever heard about the “microbiome?�? It kind of sounds like a creature from another planet. Instead, it is a collection of “creatures�? existing within each of us. Although I am no means an expert on this topic, in this short blog I’ll highlight some tidbits on this evolving research.

Within our body, and especially on our skin, in our nose, and in particular within our gut, we have around 100 trillion bacteria, fungi and viruses, collectively called our “microbiome.�? We have 10 times more of these microbial cells living in our body than our own cells. And, believe
it or not, without these microbial cells, we wouldn’t survive. Estimates vary, but it is estimated that there are over 1,000 different species of both protective and pathogenic microorganisms within our body.

Each of us has our own unique microbiome. The gut microbiome is sometimes referred to as a “second brain.�? The composition of our microbiome influences digestion, absorption, utilization of nutrients, metabolic processes, cravings, mood, behavior, and immune function.

A few things to know about the microbiome.
1. The more diverse the gut microbiome, the more protective against disease.
2. The composition of the microbiome is more diverse and protective when exposed to having a natural childbirth, being breast-fed, exposure to animals and dirt, and consuming a plant-based diet.

Important protective microorganisms are transferred to a newborn during natural childbirth and through breastfeeding. As for animals and dirt, childhood exposure to bacteria in the environment contributes to the microbiome diversity and is important for strengthening immunity.

Now my area—nutrition. The amount and type of foods we consume have a profound impact on the composition and action of the gut microorganisms. A plant-based diet has been associated with more microbial diversity (a good thing) which lowers the risk of inflammation, obesity, and diabetes. Foods such as fruits, seeds, vegetables, tea, cocoa products, and wine have an effect of increasing the number of healthy bacteria while reducing the pro-inflammatory bacteria. Unfortunately, our typical westernized diet is highly processed containing refined carbohydrates that results in reduced genetic diversity of the microbiome, a reduction of the health-promoting organisms, and an increase in organisms that promote inflammation.

So, what can you do to improve your gut microbiome? Consume more plant-based foods high in fiber similar to the guidelines of MyPlate (see www.choosemyplate.gov). Make half of your plate fruits and veggies including foods containing prebiotics which are selectively fermented ingredients that positively change both the composition and/or activity in the gut microorganisms. Prebiotic foods include leeks, asparagus, chicory, Jerusalem artichokes, garlic, onions, whole wheat, oats and soybeans. Or, simply consume more wholesome plant based products (whole grains, fruits and vegetables), and you will likely consume more prebiotics.

Non-nutritional lifestyle choices may also alter the microbiome. I’ve already mentioned children should play in dirt. For both children and adults, physical activity seems to have a positive influence on the composition and variety of our microbiome. Stress, on the other hand, seems to reduce the number of beneficial bacteria and negatively alter pathways important for health.
Lack of sleep and alterations in sleep patterns may also negatively impact our microbiome.

Research on the health impact of the microbiome is fairly new and much more research is needed (and is occurring). I’m sure there will be much more discovered about this fascinating subject in the months and years ahead.
I do find it interesting that although the new “buzz�? in science is on the microbiome, the bottom line for eating is the same: Consume a wholesome diet high in a variety of plant foods and low in processed foods. Although I want to say “dah,�? I’m glad that there are now more reasons for eating the “MyPlate�? way.

For more information:

The Human Microbiome Project: https://www.hmpdacc.org/hmp/overview/

“Dirt Is Good,�? Jack Gilbert, director of the University of Chicago Microbiome Center, and Rob Knight, director of the University of California Center for Microbiome Innovation, with science writer Sandra Blakeslee

By Eileen Stellefson Myers, MPH, RDN, LDN, CEDRD, FAND