September 29, 2014
287 Diet & Our Microbiome [29 Sept 2014]
A lecture by gastroenterologist Dr. Robynne Chutkan on MindBodyGreen.com described the inter-relationship between what we eat and our gut flora. I have previously written about antibiotic overuse and its unintended impact on our microbiome [#281 18 August 2014].
Our microbiome – the bacteria, viruses, fungi and protozoa that live in or on the human body – is composed of some 10,000 species totaling 10 trillion cells (10 times more than our body cells). We are finally realizing that the majority of these species are not only beneficial but essential for our health. Besides keeping pathogens (disease causing microbes) in check, they aid in the digestion of, and processing of nutrients from, our food.
Chutkan refers to several recent studies which clearly show how our diet affects our microbiome.
A 2009 study from Australia discovered that plant fiber is converted by bacteria in the gut to short chain fatty acids which are known to alleviate colitis and may explain how changes in diet improves symptoms of asthma, rheumatoid arthritis, and other inflammatory diseases.
A 2010 study by Dr Paolo Lionetti compared the fecal microbes of children from Florence Italy eating a typical sugar & fat-laden western diet with those of children from a rural East African village with a mostly plant-based fiber-rich diet. The African children had bacteria that promoted leanness and the production of anti-inflammatory short chain fatty acids, while the Italian kids had more species associated with diarrhea, allergies and obesity.
A 2013 Harvard study found that bacteria in the gut changed quickly, beginning the first day, when the subjects were switched from an animal-based to a plant-based diet (and vice-versa). Not only do the species of bacteria change but different genes were switched on or off, all of which affect our health.
Chutkan then describes how our microbiome also affects our diet. From the same food, gut bacteria in obese mice extract fewer nutrients but more calories than the bacteria in lean mice. This explains why, even on a healthy diet, people who are overweight can gain more weight and still be deficient in certain nutrients. Life just isn’t fair!
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.