The ecological community of bacteria, fungi, viruses and single-cell organisms living in your body are known as the microbiome, aka microbiota. These trillions upon trillions of microbes call your body home. They make up about 3% of your total body weight and are just as numerous as human cells, despite what you may have heard about there being 10 times more bacterial cells. With approximately 5000 different species living in and on you at any one time, it is believed these microbes evolved alongside us, developing a symbiotic relationship with our bodies and brains. Free will notwithstanding, it is unclear who controls whom. Recent research has shown the microbiome plays a role, although not completely understood, in these human conditions (and many others):
NOTE: Our understanding of what constitutes a healthy versus unhealthy microbiome is still evolving. Only a few associations have been established in human studies thus far. The good news is the National Institutes of Health embarked on the Human Microbiome Project. Its mission is to generate research resources enabling comprehensive characterization of the human microbiota and analysis of their role in human health and disease. Their long-term goal is ‘to develop datasets and tools that the community can use to evaluate which biological properties of the microbiome and host will yield important new insights in understanding human health and disease.’
The microbiota lives all over our body but most of it is in the gut – specifically the intestines. These gut colonies live off the food we take in. There are communities of bacteria that thrive on sugar, some that love fat, others that need protein and some that need a bit of everything. How we eat determines which communities of bacteria live and die. For example, if you take sugar out of your diet for a couple of months it’ll likely trigger a genocide in the simple carbohydrate eating bacteria population. Conversely, eating sugar on a regular basis (like the standard American diet- AKA SAD) will likely strengthen the population of these junk food loving microbes. The largest communities seem to have the most sway when it comes to our cravings. As a result, when we eat lots of sugary foods, these microflora tell the body to “feed me” and increase cravings for the food they need to live and reproduce. Some potential mechanisms by which the gut flora exert their influence:
Diet plays an important role in controlling and affecting the microbiome but so does the environment. A general shift away from natural environments with little exposure to soil, animals, and other environmental microbes seems to be impacting the gut microbiome in potentially harmful ways. For instance, children raised in homes with pets have less risk of allergic diseases and new evidence is demonstrating a link with gut microbiome patterns. Exposure to dogs and cats seems to alter the gut microbiome to be protective against allergic issues and respiratory viruses. A kiss from a dog keeps the allergies away! Besides moving to the country and filling your house with pets you can increase the diversity and strength of your microbiota by following these suggestions:
Eat a diverse cuisine, especially lots of fibrous fruits and vegetables
Steer clear of highly processed food products
Play in the park and don’t be afraid to get dirty
Eat fermented foods daily: Pickles, kimchi, sauerkraut, miso, kombucha, yogurt etc.
Eat probiotic foods like artichokes, garlic, leeks, onions, asparagus, dandelion
Eat some resistant starch like greenish banana, lentils, green beans, rolled oats
Limit antibiotics in foods and medicines you take.
Fecal transplants also show promise – but this is the last resort!
NOTE: The science on probiotic supplementation for healthy individuals is weak at best. Watch this short clip:
So who is in control, you or your microbiome? Perhaps it’s a two-way street. If we can, in fact, exert influence over the microbiome, why not starve those sugar craving critters, repopulate your gut with a diverse army of ‘healthy’ bacteria and take back control.