The MicrobiomeQuite a lot of people do not like to share their space. It's understandable that some are uncomfortable when a conversation, as with a stranger, is carried on to close for comfort. There is, however, an instance where closeness cannot be avoided with the microbiome that occupies not only our space, but also us. The human body holds ten times more microbes than human cells, some on the outside, and others on the inside. The skin, the largest organ of the body, houses a range of microbes that live in distinct communities yet work together to protect us from attack by sickness and disease (Grice, 2009). But our attention here is to those on the inside, the microbiota that weigh up to three pounds and contain tens of trillions of members. There might even be more than a thousand different species, about a third of which are common to most of us. The other two-thirds belong only to you.
Though we have a tailor-made personal microbiome, all perform the same physiological functions and have a direct impact on our health. Besides completing digestion by absorbing water and storing wastes, the gut microbes help to make biotin and vitamin K while fighting aggression from the pathogenic gang of bugs and bolstering the immune system. Each of our gut communities remains stable throughout our lives, unless dietary changes are dramatic. Those who consume lots of vegetables and fiber have a different composition from those who live on fatty meats and simple carbohydrates. What happens in the gut telegraphs to what happens in other areas of the body, including areas that manage mood and possibly the onset of chronic and degenerative diseases (Tillisch, 2013).
The neonatal biome starts to form right after birth, when the digestive tract becomes colonized by micro-organisms that come from the mother and from the environment into which it is born. In about three years the biome becomes stable. To keep it that way, we need to take measures that transcend dietary behavior and the mere swallowing of probiotics as adults. Probiotics are micro-organisms. To analogize, they're like police whose local precinct needs a workplace conducive to efficiency. If a probiotic, or any array of gut bacteria for that matter, is to augment or to enhance the native population, it needs a favorable place to work. The problem with the typical Western diet is that we feed the upper GI tract without feeding the gut. One way to do that is with resistant starch, the fermentation of which manufactures short-chain fatty acids, notably butyrate. Butyrate nourishes the gut barrier and helps to support a healthy inflammation response*. Very often, however, dietary intake of resistant starch is insufficient to make enough butyrate to be physiologically significant.
What Does Butyrate Do?
What does butyrate do? It has powerful effects on several colonic functions, not the least of which is supporting a healthy inflammation response and reinforcement of the defenses that fight infection and oxidative stress (Hamer, 2008)*. Butyrate has partners and precursors in the form of acetates and propionates, likewise made by the bacterial fermentation of resistant starch and fiber. In the company of acetate, butyrate is reported to protect against diet-induced obesity without causing hypophagia, while propionate may reduce food intake*. Unfortunately, there is little understanding why this works (Hua, 2012). What distinguishes one from another? The number of carbons it holds. Acetic acid has two, propionic acid has three and butyric acid has four. The first of these has the scent of vinegar. Propionic acid is found in sweat; butyric acid in rancid butter and vomit.
Butyrate, joined with calcium, magnesium, potassium, sodium or a combination of these minerals inhibits histone deacetylase enzymes, helping butyric acid to enhance the transcription activity of DNA*. If this activity of the butyrate molecule has been known since the late 1990's, why has it not received the publicity that newly-concocted drugs, with their hosts of nasty side effects, have?
The reasons for paying attention to your gut go beyond what you read while seated. Some problems can be attenuated with an occasional laxative, although increasing dietary fiber is a better technique. Even the orange-flavored stuff in the plastic canister, used every day, is an improvement. But a butyrate supplement, despite its pungency, is the best thing going, especially as we get older.
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*These statements have not been evaluated by the FDA. These products are not intended to treat, diagnose, cure, or prevent any disease.