Protein Supplements and Their Relation with Nutrition, Microbiota Composition and Health: Is More Protein Always Better for Sportspeople?

Abstract

Sports nutrition products are developed and targeted mainly for athletes to improve their nutrient intake, performance, and muscle growth. The fastest growing consumer groups for these products are recreational sportspeople and lifestyle users. Although athletes may have elevated physiological protein requirements and they may benefit from dietary supplements, the evidence regarding the role of dietary protein and supplements in the nutrition of recreational sportspeople and sedentary populations is somewhat complex and contradictory. In high-protein diets, more undigested protein-derived constituents end up in the large intestine compared to moderate or low-protein diets, and hence, more bacterial amino acid metabolism takes place in the colon, having both positive and negative systemic and metabolic effects on the host. The aim of the present review is to summarize the impact of the high-protein products and diets on nutrition and health, in sportspeople and in sedentary consumers. We are opening the debate about the current protein intake recommendations, with an emphasis on evidence-based effects on intestinal microbiota and personalized guidelines regarding protein and amino acid supplementation in sportspeople and lifestyle consumers.

A Review of the Role of the Gut Microbiome in Personalized Sports Nutrition

“…Although studies have shown some dietary interactions with the gut microbiome in athletes, it is unclear the extent to which the gut microbiome might be affected by supplements or dietary patterns commonly used by athletes, and the potential effects of this on the host. A review by Kårlund et al (97) comprehensively discusses the topic of protein supplementation in athletes and the potential unknown effects on the gut microbiome. Excess protein may be fermented in the large intestine by various species from the genera Clostridium, Bacteroides, and others from the animal-based diets have also been shown to induce differences in the gut microbiome composition in humans (16).…”

“…Additionally, different protein types have been assessed in the context of the anabolic response to exercise (105). However, there are no studies evaluating the impact of different types of protein supplements or whole-food protein sources on the gut microbiome and amino acid fermentation in athletes (97). As protein and protein supplements are widely advertised and recommended to athletes, this is an important gap in the research that should be addressed.…”

Mutual Interactions among Exercise, Sport Supplements and Microbiota

“…Microbial diversity has been found to positively correlate with protein intake and exercise in elite athletes [63], and thus, exercise training is suggested to be essential for healthy and balanced gut microbiota, and muscle mass and function. According to these observations, well-balanced protein intake should support not only athletic performance but also the well-being of the gut [187]. Although the physiological dietary protein requirements are elevated for athletes, high-protein diets may affect the gut microbiota and protein fermentation levels [94], with consequences for health [187].…”

“…According to these observations, well-balanced protein intake should support not only athletic performance but also the well-being of the gut [187]. Although the physiological dietary protein requirements are elevated for athletes, high-protein diets may affect the gut microbiota and protein fermentation levels [94], with consequences for health [187]. Effects of protein supplementation for microbiota in athletes should be taken into consideration since nutritional recommendations regarding protein consumption in this population are higher than for the general population.…”

The Dysbiosis of Gut Microbiota Caused by Low-Dose Cadmium Aggravate the Injury of Mice Liver through Increasing Intestinal Permeability

“…It has been confirmed that gut microbiota is involving in a host's health throughout life [12]. Its functions include the production of nutrients, immune response, and protection from infections [13,14]. However, the dysbiosis of gut microbiota increases intestinal permeability and drives inflammation and mortality [15,16].…”