Recipe to Try: Prebiotic-Rich Chicken & White Bean Soup with Leeks
What if you had an organ you didn't know existed? Trillions of microorganisms live in your gastrointestinal (GI) system, and this host of bacteria is often considered the "forgotten organ." Like other organs of the body, this group of bacteria, sometimes called the gut microbiome, has to be cared for. It can even get sick, which produces ripple effects of symptoms.
The GI system and gut microbiome have only recently come to the forefront of health discussions. As more and more researchers connect the dots between the role the gut plays in human health, doctors are discussing the importance of caring for your gut health as a way of caring for your overall health. In fact, preliminary studies link the health of the gut microbiome to immunity, development of chronic diseases like diabetes and heart disease, digestive health, and even your mood.
Read More: How Gut Bacteria Can Transform Your Health
Understanding what the gut microbiome is—and what it isn't—can help you understand better ways to care for it. You can have an impact on your microbiome's health, and here's how.
The gut microbiome consists of living microorganisms (aka microbiota or microbes) working in conjunction with each other to perform various functions. These functions include digestion, nutrient absorption and energy metabolism. The microbes can ferment and break down nondigestible foods and convert them into substances that can be used for energy.
More than 1,000 types of gut microorganisms have already been identified. That number is likely to grow, however, as researchers better understand the gut microbiome. The majority of the gut microbes live in the colon, and gut bacteria amounts and diversity shift throughout life. The greatest shifts occur within the first two years of life, from infancy to childhood. After age two, the gut microbiome stabilizes and remains largely unchanged until advanced age. But throughout life, various factors, such as health status and antibiotic usage, can influence the gut bacteria balance.
Not everyone's gut microbiome is the same, nor should it be. Some known influences on an individual's micobiome composition include genetics, type of delivery at birth (cesarean section versus vaginal birth), antibiotic use, age, health status, geographic location, stress level, frequency of exercise and diet. So, while some factors may be out of your control, others can actually be influenced by diet and lifestyle.
Read More: 5 Ways to Improve Your Gut Microbiome
Two compounds, prebiotics and probiotics, are key players in boosting your gut bacteria's health. Having a healthy balance of the two in your microbiome is essential for maintaining good health—both in your gut and overall. The good news is, you can find foods and drinks that contain both of these compounds, so creating a healthier microbiome is possible and can even be delicious.
Probiotics are living microorganisms that live within certain foods. Fermented foods, such as kombucha and sauerkraut, are often rich sources of probiotics, as are cultured dairy foods, like yogurt and kefir. It's important to not buy pasteurized versions of these foods, however. The pasteurization process heats and destroys the good-for-your-gut bacteria.
Probiotic benefits are not a recent discovery. Throughout history, even before the individual microorganisms were fully understood, many cultures featured fermented foods in traditional cuisine—Korean kimchi, Japanese miso and Chinese sauerkraut, just to name a few. We now know that these fermented foods contain probiotics, beneficial bacteria for the gut microbiome.
Probiotics are perhaps the more well-known of the two compounds, but the lesser-known prebiotics may be even more important for gut health. Prebiotics are the precursors to the proper maintenance of the gut's bacteria balance. Prebiotics are nondigestible food compounds that microbes eat for better health. In other words, microbes need prebiotics for fuel. The more prebiotics in your gut, the more energy the gut bacteria have to grow and stay healthy. The important working relationship between probiotics and prebiotics is one of the reasons why they're often referred to as the "dynamic duo." Some common food sources of prebiotics include garlic, onions, wheat, bananas, leeks, artichokes and oats.
Research shows that plant-based, fiber-rich diets boost the diversity of microorganisms in the gut. Ultimately, the greater the diversity of the bacteria, the greater the beneficial outcomes.
The good news is, bacteria can be altered by diet alone. That means you do not need to purchase over-the-counter high-dose probiotic supplements. (A few exceptions to this include people with chronic conditions, such as irritable bowel syndrome or Crohn's disease, as well as people who are taking high-dose antibiotics or have another condition that impacts the GI tract. If you have any of these conditions, talk with your doctor about the best way to boost your gut microbes.)
The benefits of eating for better gut health may occur rapidly, too. Research into the effects of food on the microbiome found that bacteria can shift in a short time span, as little as five days. A small study published in Nature in 2014 found that people who ate a plant-based diet had altered gut bacteria compared to people who ate an animal-based diet. This study found that the shift in the guts of the plant eaters happened rapidly, and despite these dramatic shifts, the clusters of healthy bacteria remained stable and thriving. These short-term studies are important, as other studies have emphasized that the long-term dietary pattern actually has the most impact on the microbiome.
The same study in Nature also found an increase in a specific type of bacteria that has been linked to the development of inflammatory bowel disease in the people who ate the animal-based, high-fat diet. Alternately, research shows that a high-fiber diet can produce variations in bacteria that lead to beneficial outcomes such as reducing inflammation. More research is needed to duplicate and understand these findings.
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Gut health matters. And a more plant-based, fiber-rich diet is essential to maintaining the diversity—and health—of the gut microbiome. Shifting away from the typical Western diet, which is low in fiber and high in fat, and toward a diet incorporating plenty of prebiotic- and probiotic-containing foods can help improve your GI system and your overall health.