A bellyful of bacteria sounds like a horror story. But we're not talking about Invasion of the Body Snatchers— there really are hundreds of trillions of microbes making themselves right at home in every person’s digestive tract.
And as gross as it sounds, this gut microbiome of bacteria is essential to overall health. Scientific studies have shown live bacteria can give depressed people a renewed will to live. Even yogic tradition holds that emotional and physical pain all gets stirred up in the gut, according to yoga instructor Meital Bat Or.
Wondering how exactly stomach issues can affect the rest of the body? Here are five physical manifestations of the power of gut health.
Healthy gut bacteria controls the body’s response to carbohydrates—either turning them into fat or into energy. Since obesity has been correlated to a lack of diversity of bacteria in the gut, diversifying the gut microbiome is key to decreasing body fat. Altering microbiota within the digestive system can allow for better fermentation of carbohydrates, making it easier to burn carbs, and reduce risk of obesity and type II diabetes.
How to do it? Keeping the home closed to the elements limits the types of microbes within the home, and this can affect the inhabitants' gut diversity. So simply opening a window and allowing air to flow in and out—and more species of bacteria along with it—can facilitate a transformation of a person's gut microbiome to contain a more diverse community of bacteria, which contributes to overall better digestive health.
The gut is home to 70 percent of the body’s immune tissue, so it follows that it must play a role in immune responses and corresponding inflammation. According to functional medical practitioner Chris Kresser, when leaky gut syndrome occurs and large protein molecules enter the bloodstream, the body engages an immune response that can trigger inflammation.
To heal leaky gut, take probiotics or olive leaf to boost healthy bacteria. Glutamine, a nutrient commonly found in bone broth, can help to repair the intestinal wall. To ease inflammation, consume some anti-inflammatory omega-3s in the form of wild salmon, fish oil, flax seeds, or chia seeds.
Thyroid and hormones
As if leaky gut-induced inflammation weren't bad enough, some experts also say it can impair thyroid function and potentially lead to Hashimoto’s disease, an autoimmune condition in which the immune system attacks the thyroid. And since the thyroid gland resides within the endocrine system, which produces hormones, hormonal balance can be affected as well.
Gluten could be a possible trigger of leaky gut and the resulting inflammation. For some people, cutting gluten may improve thyroid health, so try an elimination diet to see if stomach troubles improve on a gluten-free diet.
Brain and mental health
The gut-brain connection is so complex that some scientists refer to the gut as the “second brain.” It’s happened to the best of us—stress can often come with a side dish of that stomach-churning feeling also known as indigestion. That could be partially because 90 percent of serotonin, a neurotransmitter linked to maintaining mood balance, is produced in the gut.
More and more studies are emerging about fermented foods’ ability to curb anxiety and probiotics’ potential to cure depression. So, eating foods such as sauerkraut, kimchi, miso, plain or Greek yogurt, soft cheeses, kefir, and kombucha could help boost mental health.
A 2013 study published in The Journal of Cancer Research found that there is a correlation between types of intestinal microbiota and the likelihood of developing lymphoma. Another 2013 study showed that some unhealthy gut bacteria may cause stomach cancer by impairing the immune system from regulating inflammation in the stomach lining. This illustrates the importance of maintaining a gut microbiome with plenty of healthy bacteria, which can be done by consuming probiotics.
And in case of a cancer diagnosis, gut bacteria can also influence the effectiveness of immunotherapy and chemotherapy, according to researchers from the National Cancer Institute—more evidence that the gut plays such an enormous role in overall health.
Aside from eating fermented foods, what are other ways to keep gut health in check? Load up on prebiotic foods with lots of soluble fiber as well, including oatmeal, lentils, beans, and fruit; these foods ferment in the colon and feed the healthy bacteria there. If possible, avoid antibiotics, which not only destroy bad bacteria, but often kill the good guys, too.
Illustration by Karley Koenig