The gut microbiome is receiving a lot of attention in the functional medicine world, and for good reason. It encompasses the bacteria, fungi, protozoa, and viruses that live in our gastrointestinal tract and are responsible for a wide range of critical processes in the human body. The gut produces neurotransmitters, including 95% of our serotonin, that play an essential role in regulating mood and mental health. It contains 70% of the cells that make up our immune system and is home to over 100 trillion bacteria. That's right; you are made up of 10x more bacterial cells than human cells!
We need a variety of “friendly” bacteria in the right balance to promote wellbeing. Without this, the gut is in a state of dysbiosis, which can manifest as gas, bloating, diarrhea, constipation, impaired metabolism, inflammation, illness, and disease. Fortunately, we have the power to modulate our microbiota with the choices we make every day. Lack of exercise, stress, medications like antibiotics (including those we ingest by eating factory-farmed meat), and a diet low in fiber and high in sugar negatively impact your microbiome. A healthy diet, exercise, and stress management are as good for your gut bacteria as they are for you.
To optimize your microbiome, regularly eat probiotic- and prebiotic-rich foods. The term probiotic is derived from Greek, meaning "for life," and refers to a living microbe that is beneficial to our health when it resides in or on our bodies. Traditionally fermented foods go through a process called lacto-fermentation. This process preserves the food by inhibiting the growth of harmful bacteria and creates probiotics, beneficial enzymes, B vitamins, and anti-inflammatory omega-3 fats. Probiotics modulate appetite, metabolism, and weight, and are associated with a reduction in rosacea, constipation, diarrhea, reflux, candida, vaginal infections, food allergies, and even food allergies in children when their mother's supplement with probiotics during pregnancy. The right strain of probiotic supplement can help alleviate specific symptoms, but it is also beneficial to eat probiotic-rich foods regularly. The best food sources include yogurt and aged cheese with live or active cultures, kefir, coconut yogurt and kefir, kimchi, kombucha, sauerkraut, miso, tempeh, and pickled fruits or vegetables. Unfortunately, not all fermented foods contain probiotics - beer and wine don’t count!
Once you populate your gut with probiotics, it's essential to eat prebiotics so the beneficial bacteria can survive. Prebiotics are fermentable starches that our gut microbes feed on, think of them as fertilizer for your garden. Prebiotic-rich food sources include garlic, onions, banana, asparagus, dandelion greens, Jerusalem artichoke or sunchokes, chicory root, leeks, and wheat bran.
Warning, for some people, increasing these otherwise healthy foods may cause worsened symptoms of gas, bloating, and other gastrointestinal discomforts. If this happens for you, it may be a sign you have dysbiosis or bacterial overgrowth that you should address first. Temporarily hold off on incorporating these foods and probiotic supplements until you consult with a doctor or a nutritionist specializing in gut function. With the proper guidance, you and your gut bacteria will thrive.