Those gut microbes are one busy “organ!” Aside from honing our immune system, balancing our metabolism, protecting our gut lining, neutralizing pathogens, and helping our brain function, did you know that these little critters are also making nutrients for us to use…
One such nutrient is folate, which is a critical nutrient for methylation pathways that are essential in every cell. Methylation is a fundamental way in which our body regulates DNA expression, through “epigenetic” control mechanisms. Methylation is also vital for the synthesis of neurotransmitters, detoxification, balancing hormone levels, clearing excess histamine, and preventing neural tube defects such as spina bifida. Bifidum species of microorganisms, especially bifidobacterium bifidum and Bifidobacterium infantis, have been shown to be particularly active in the production of folate. Bifidobacterium breve, Bifidobacterium longum and Bifidobacterium adolescentis are also folate producers.
Vitamin K is another essential nutrient which is produced in a happy gut and is most well-known for its role in blood clotting. However, another lesser-known but very important role for this vitamin is in bone health, since the enzymes that create bone have to be activated by another vitamin K-dependent enzyme. Prolonged antibiotic therapy has been shown to lead to vitamin K deficiency, suggesting that the role of bacteria in vitamin K supply for the body is rather significant.
In addition to folate and vitamin K, certain gut bacteria also appear to be active producers of B vitamins essential for cellular energy metabolism and the utilization of carbohydrates, fats and proteins. These macronutrients go on to form the building blocks for all our body’s systems and so their proper use is fundamental to our health. By examining the DNA sequencing of gut microbes, we now know that thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), cobalamin (B12), and biotin can all be produced by these little bugs. Interestingly, too, most of these vitamin-synthesizing capabilities reside in the Bacteroidetes phylum of microbes; which may be one reason why a higher ratio of Bacteroidetes to Firmicutes has been associated with a healthier gut microbiota and lower prevalence of obesity. Your functional medicine doc can identify these ratios in stool tests and work to adjust them.
Putting this into context – while dietary nutrients still fulfill the majority of our daily requirements, microbes in our gut are likely to be an additional important source. We should take care to keep their populations balanced and well-nourished!
LeBlanc JG, et al. 2012. Bacteria as vitamin suppliers to their host: a gut microbiota perspective. Current Opinion in Biotechnology. 24:1-9.