Study shows a short-term, high-protein diet can change your gut microbiome

Highly-trained endurance athletes were shown to display “microbial instability” in their gut when they followed even a short-term high protein diet, report researchers from Anglia Ruskin University (ARU) in the American Society for Microbiology’s journal mSystems. 

This gut disturbance was accompanied by a 23.3 per cent drop in time trial performance on a treadmill test, says Justin Roberts, associate professor in Health and Exercise Nutrition at ARU and co-author of the study. Conversely, when athletes followed a short-term, high-carb diet, their time trial performance was boosted by 6.5 per cent.

Roberts and his team assessed microbiome imbalance by analysing the diversity and altered composition of the gut, as well as monitoring levels of viruses and bacteria present. 

In some people gut disturbance can cause cramps, nausea and sickness.

“While we cannot be certain that the high amount of protein in the body was entirely responsible for the significant drop in time trial performance, it was found that there were certainly changes to the gut microbiome following a short-term, high-protein diet which appeared to be associated with performance,” he says. 

“These results suggest that consuming a high-protein diet may negatively impact the gut via an altered microbial pattern, while a high-carbohydrate intake, for example containing a variety of grains and vegetables, was associated with greater gut microbial stability.”

READ MORE: Antibiotics lower endurance and motivation

Since the diets were carefully balanced it is unlikely that protein itself was to blame for the downturn in performance. “Instead, we think it is possible that the changes to the gut microbiome could impact intestinal permeability or nutrient absorption, or the messages between the gut and the brain, affecting perceived effort and therefore performance,” Roberts says.

Royal jelly CO-Q10 combo brings down muscle damage

Supplements of bee-derived royal jelly and Co-Q10, a molecule that plays a key role in supplying energy to cells, can help to reduce oxidative stress and muscle damage, enhancing performance in elite athletes, according to scientists from Lobachevsky University in Russia reporting in the International Journal of the Society of Sports Nutrition. Both ingredients have potent antioxidant activity and CoQ10 is known to activate AMPK, an enzyme that increases cell survival in the body.

“Co Q10 and some RJ components contain medium chain fatty acids, amino acids, proteins, flavonoids and phenolic compounds which have antioxidant properties,” the researchers write. For their trial, they provided 20 elite swimmers with either 400mg of royal jelly and 60mg of CoQ10 (RJQ) or a placebo once daily for 10 days. Results showed that during and immediately after high intensity interval training “reduced muscle damage in the swimmers and improved their exercise performance”.

Why hunger is held at bay after a tough session

Molecule released in higher amounts during intense exercise seems to stifle appetite and explains why athletes don’t feel hungry immediately following an intense training session, suggests an international team of researchers reporting in Nature journal. 

Gareth Wallis, associate professor of exercise metabolism and nutrition at the University of Birmingham, one of the scientists involved in the research, says the molecule called Lac-Phe is a hybrid of the compounds lactate and phenylaninine that are produced during intense activity.

Eight male athletes were asked to exercise three times – performing a gentle, continuous bike ride of 90 minutes, an indoor bike session with intermittent 30-second sprints or weight training – with blood samples taken during and after each session.

Results showed the interval sprints induced the most dramatic spike in blood levels of
Lac-Phe, followed by resistance training, with the long, slow cycle producing the lowest levels of the molecule. “We know from animal studies that more Lac-Phe leads to fewer calories consumed, a natural conclusion would be to assume that it is involved in the suppression of hunger,” Wallis says.

» This article first appeared in the August issue of AW magazine. To subscribe, CLICK HERE