Bacterial Diversity Is a Biomarker of Gut Microbiome Health
Diversity is an important thing. Ethnically diverse cities like New York City, San Francisco, and Seattle are productive economic hubs and sought-after tourist destinations. Well it turns out, diversity among the 100 trillion bacteria we call our gut microbiome is a good thing, too. Researchers in Ireland wanted to find out what impact extreme exercise and dietary habits had on the diversity of the gut microbiome. So, they chose people who exercise a lot—rugby players. They added two control groups to the study: lean individuals, who exercise occasionally, and overweight, sedentary individuals—or normal and high BMI controls.
A High-Calorie, High-Carbohydrate Diet Didn’t Negatively Impact the Gut Microbes of Exercising Athletes
The diets and the gut microbes between the three different study sets were analyzed to see what impact calorie and macronutrient composition had on bacterial diversity and bacteria in the gut. Surprisingly, the exercising rugby players, despite eating more calories, harbored gut microbes that were exceedingly diverse. On average, the rugby players consumed nearly 4,500 calories per day, 250 grams of protein per day, and more than 500 grams of carbohydrates per day. Based on previous studies, which have shown that a diet rich in calories and carbohydrates has a deleterious impact on the gut microbes of humans, it’s natural to assume that this diet would have been similarly unfavorable for these athletes. Not so.
Although the lean and overweight controls consumed roughly 40 percent less calories and carbohydrates and more than 50 percent less protein than the rugby players, the health of their gut bacteria was not favorable. The bacterial diversity in the rugby players was found to be twice as diverse in the number of phyla, families, and genera of bacteria compared to the control groups. Upon further inspection of the diets between these groups, the athletes consumed a lot more vegetables, fruit, and protein. In contrast, the controls ate a lot of snacks. Since most ready-to-eat snack food is processed sugar and fat, it’s probable that this factor played a role in the reduced microbiome diversity in the control groups.
High-Protein Diets Are Thought to Favor the Growth of More Healthy Gut Bacteria
The researchers took a deep dive into the microbial composition of the diets and revealed an interesting and significant finding: the athletes consumed 2.36 grams per kilogram of body weight (g/kg/bw) in protein, while the controls only consumed between 1 and 1.5 g/kg/bw in protein. Moreover, the athletes consumed ample supplemental whey protein. Although protein fermentation in the gut can create damaging by-products like ammonia, whey protein is metabolized differently, according to scientists. It has been shown that the type of foods you eat a lot of can change the metabolism of the bacteria in your gut. Eat a lot of carbs, you’ll enrich the types of bacteria in your gut that are efficient carbohydrate metabolizers. Along these lines, this study reported another interesting finding in the high-protein–eating athletes: they had significantly higher levels of the bacteria from the Akkermansia genus. High levels of these mucus-degrading bacteria are protective against metabolic disease, and the levels are linked with a decreased risk of obesity.
Summary and Conclusion
In summary, we can conclude that a highly diverse diet equals a highly diverse bacterial ecosystem. So stop counting calories and start focusing on food diversity!
Clarke, S. F., Murphy, E. F., O'sullivan, O., Lucey, A. J., Humphreys, M., Hogan, A., et al. (2014). Exercise and associated dietary extremes impact on gut microbial diversity. Gut. doi:10.1136/gutjnl-2013-306541