If the bacteria living in your intestinal tract are healthier, will they use more of the calories you eat? A January 2023 publication in the journal Nature Communications addresses this.

    The study, titled “Host-diet-gut microbiome interactions influence human energy balance: a randomized clinical trial,” was very carefully done. A group of healthy men and women entered a metabolic ward, where they had no access to food or beverages other than what the researchers provided. They received two different diets, equal in calories, a “Western Diet” and a “Microbiome Enhancer Diet.” After 6 days on each of these two diets, various tests were done and compared.

    Even though the intervention was short, the Microbiome Enhancer Diet increased the number of types of bacteria in the microbiome and the amount of fermentation products they made, both of which are beneficial changes. These healthy bacteria used about 100 calories more than the bacteria in the Western Diet segment of the study. While eating the Microbiome Enhancer Diet, even though their bodies received fewer calories, study subjects were no hungrier, and their metabolism did not slow down.

    What did the Microbiome Enhancer Diet consist of? It had four components: dietary fiber, resistant starch, large food particle size, and limited processed foods. Fiber is not digested by human enzymes, so it reaches the large intestine intact and provides fuel for the bacteria. Resistant starch resists digestion in the small intestine, and so is available in the large intestine for microbes; foods high in it include oats, brown rice, and beans. As an example of the distinction between large and small particle size, nuts were included in the Microbiome Enhancer Diet, nut butters were not.

    While the diets I recommend may vary in the amount of animal protein included and in the types of vegetables eaten, all of them encourage the consumption of the foods I just listed.

    The office will be closed on Monday, January 15, 2024 in observance of Martin Luther King Day.