This is really big! In an elegantly conducted clinical trial by one of the world’s most esteemed microbiome scientists we find that stepping up the intake of fermented foods is a quick and effective way to boost gut microbial diversity AND decrease damaging inflammation—even more so than stepping up your intake of fiber-rich plant foods! For this landmark study, 36 healthy adults were placed on one of two test diets. One diet group consumed a diet enriched with a variety of fermented foods (ultimately ramping up to about 6 servings a day), and the other study group consumed a high fiber diet (about 40 grams a day). Each study subject had their stool and blood monitored prior to, during, and up to four weeks after the test diets. The researchers were specifically tracking the microbial species within study subjects’ stools (a proxy for those in the gut) as well as numerous blood markers for inflammation. The results were eye-opening! Eating the fermented foods – yogurt, kefir, kimchi, kraut and other fermented veggies, kombucha, and fermented cottage cheese lead to a significant increase in gut microbial diversity— the most telling sign of a healthy gut microbiome! Those on the high fiber diet from beans, nuts, seeds, whole grains, fruits and veggies did not show increases in gut microbial diversity. In those consuming the fermented food diet, four types of proinflammatory immune cells diminished in activity. Additionally, there was a significant decrease in levels of 19 various inflammatory blood proteins, including the infamous interleukin 6 or “IL6.” IL6 is implicated as a key driver of numerous inflammatory-based diseases including autoimmune conditions, IBD, acne, type 2 diabetes, arthritis, death from covid, and depression, amongst others. Those on the high fiber diet did not show any significant changes to markers of inflammation. These results were consistent across all study subjects, which adds to the veracity of the data. According to the lead scientist, Stanford’s Justin Sonnenburg, PhD, these findings are “stunning.” They show that stepping up the intake of fermented foods quickly boosts gut microbial diversity and results in significant reduction of damaging pro-inflammatory compounds. Folks, this is so encouraging! Go stock your fridge with a variety of fermented foods and include them daily as part of a healthy diet. Keep in mind that a serving is smaller than you may realize – just two tablespoons of kraut or a couple of ounces of kefir. You have absolutely nothing to lose and perhaps a ton to gain. But don’t forget the plant-based fiber foods too—fiber is what sustains the good gut changes! |
Cell, 2021; DOI: 10.1016/j.cell.2021.06.019