David Perlmutter, MD interviews Gerard Mullin, MD about the Importance of the Microbiome

David Perlmutter, MD interviews Gerard Mullin, MD about the Importance of the Microbiome

Recently, Dr. David Perlmutter (author of Grain Brain and Brain Maker) interviewed Dr. Gerard Mullin, director of Integrative Gastroenterology Nutrition Services at The Johns Hopkins Hospital, and expert in the gut microbiome and gut health. The interview can be seen on YouTube.

In this fascinating interview, Dr. Mullin elaborates upon the importance of a healthy and diverse population of gut bacteria for weight loss, balanced immunity, and the avoidance of many diseases, including diabetes, asthma, cardiovascular disease, and autoimmune disease. He discusses the damage incurred by the overuse of medications such as antibiotics, proton pump inhibitors (PPI’s), and non-steroidal antiinflammatories (NSAIDS). For example, PPI’s, which are among the top 3 classes of medication prescribed and sold in the US, function by reducing stomach acid. Unfortunately, we need stomach acid in order to keep the upper GI tract sterile, so these drugs lead to colonization of the gut with bad bacteria (small intestinal bacterial overgrowth), which disrupts the microbiome.

70% of the antibiotics used in this country go towards fattening up commercially raised cattle for profit. This leads to the development of “super bug” epidemics that we simply do not know how to handle. These drugs disrupt the microbiome of the animals, which in turn disrupts our guts. Although small, the amount of antibiotics in the meat we eat is sufficient to make us fat, and can have long lasting negative consequences on our overall health.

NSAIDS cause injury to the lining of the gut, which leads to a condition called “leaky gut” in which toxins leak out of the intestinal wall, causing an inflammatory cascade throughout the body which eventually becomes chronic, and can lead to many of the diseases mentioned above.

Dr. Mullin stresses the importance of a healthy diet, rich in vegetables, clean sources of protein (e.g. meats that have not been treated with antibiotics), and fermented foods, to help the gut to heal and encourage the “good” bacteria to flourish. He explains how a disrupted microbiome (“dysbiosis”) can affect appetite, insulin sensitivity and insulin resistance, which lead to weight gain. Not a fan of crash or fad diets, he believes that the first step towards healthy weight loss is to revamp the gut bacteria.

While Dr. Mullin is a proponent of obtaining probiotics from food sources due to the scarcity of high quality probiotics generally available to the consumer, getting adequate amounts from diet alone is a daunting and probably unrealistic challenge for the average American, unaccustomed to eating large quantities of fermented foods. However, excellent encapsulated products may be obtained through some medical practitioners. One example is Physician Nutrients® Probiotic Daily Dairy Free, or the more potent Physician Nutrients® Probiotic 100B Dairy Free. Both of these products contain well researched and genetically identified bacterial strains, and are conveniently packaged in nitrogen sealed foil packets which do not require refrigeration.

His new book, The Gut Balance Revolution, expands upon the issue of the microbiome and provides the reader with the tools and information necessary to promote good health and a healthy weight by protecting our “inner gardens.”


These statements have not been evaluated by the Food and Drug Administration.  These products are not intended to diagnose, treat, cure, or prevent any disease.

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