Strength training can help to mitigate some of the health hazards linked with a high-protein diet. While a high-protein diet might promote muscle building, satiety, and weight management, it can also pose some health risks if not appropriately balanced. According to new research in mice, progressive strength training with resistance can guard against the negative consequences of a high-protein diet.
The study, which was published as a Reviewed Preprint in eLife, reveals what the editors call a valuable result on the interaction between a high-protein diet and resistance exercise on fat storage and glucose homeostasis, which is backed by good evidence. The findings, they add, will be useful to dietitians and others working to understand the relationships between dietary protein, diabetes, and exercise.
Dietary protein contains critical nutrients that regulate a wide range of bodily processes and can influence health and lifespan. Protein consumption is typically regarded as beneficial in terms of encouraging muscle growth and strength, particularly when accompanied with exercise. However, in sedentary persons, too much protein can increase the risk of heart disease, diabetes, and mortality.
Our findings suggest that resistance exercise protects mice from high-protein-induced fat gain. This shows that metabolically ill, sedentary persons who consume a high-protein diet or take protein supplements may benefit from either reducing their protein intake or increasing their resistance activity.
Dudley Lamming
“We know that low-protein diets and diets with reduced levels of specific amino acids promote healthspan and lifespan in animals, and that short-term protein restriction improves the health of metabolically unhealthy, adult humans,” says lead author Michaela Trautman, Research Assistant at the Department of Medicine, School of Medicine and Public Health, University of Wisconsin, US.
“But this presents a paradox — if high dietary protein is so harmful, many people with high-protein diets or protein supplements would be overweight and at an increased risk of diabetes, whereas athletes with high-protein diets are among the most metabolically healthy.”
The researchers used a progressive resistance-based strength training program in mice to investigate the idea that exercise can guard against the negative effects of a high-protein diet. For three months, the animals drew a cart carrying an increasing load of weight along a track three times per week, or they pulled an identical cart with no load. A low-protein diet (7% of calories from protein) was fed to one group of mice, while a high-protein diet (36% of calories from protein) was fed to the other. The team then examined the three groups’ body composition, weight, and metabolic parameters, such as blood glucose.
The results were as expected: a high-protein diet harmed metabolic health in inactive mice that weighed nothing; these mice gained excess fat mass when compared to low-protein diet mice. A high-protein diet, on the other hand, led to muscle building, particularly in the forearm, and prevented the mice from acquiring fat. The exercise, however, did not protect the mice from the effects of high protein intake on blood sugar management.
Furthermore, despite the fact that the mice given high-protein diets gained strength faster than the mice fed low-protein diets, there was no difference in the maximum weight each group of mice could pull by the conclusion of the study period, despite the fact that the mice fed high-protein diets were bigger and had stronger muscles.
Although the data supporting the study’s claims was deemed solid, the editors point out a handful of shortcomings. Because of intrinsic physiological distinctions, the use of mice may limit the generalizability of the findings to humans. The editors add that including a direct examination into the underlying molecular mechanisms responsible for the observed results will strengthen the findings even further.
“We know that many people deliberately consuming high-protein diets or consuming protein supplements to support their exercise regimen are not metabolically unhealthy, despite the body of evidence showing that high-protein levels can have detrimental metabolic effects,” says senior author Dudley Lamming, Associate Professor of Medicine (Endocrinology) at the Department of Medicine, School of Medicine and Public Health, University of Wisconsin.
“Our findings suggest that resistance exercise protects mice from high-protein-induced fat gain. This shows that metabolically ill, sedentary persons who consume a high-protein diet or take protein supplements may benefit from either reducing their protein intake or increasing their resistance activity.”
