The Rundown

Strength Training & High Protein. Does exercise protect against the detrimental effects of a high-protein diet? A new paper published as a Reviewed Preprint in eLife, investigates the paradox of how high-protein diets are healthy in athletes but increase disease risk and reduce lifespan in others.

Consuming protein is generally a good thing, as it promotes muscle growth and strength. But in people with a sedentary lifestyle, too much protein can increase the risk of heart disease, diabetes and death. The researchers for this study turned to mice and a progressive resistance-based strength training program to explore the mystery.

The mice either pulled a cart with an increasing load of weight down a track three times a week for three months or pulled an identical cart without any load for the same time period. One group were fed a diet low in protein (7%) while another were fed a high-protein diet (36%).

As expected, the high-protein diet group that pulled no weight had poor metabolic health and gained excess fat mass compared to the low-protein diet mice. In mice pulling the increasingly weighted cart, the high-protein diet resulted in muscle growth and they did not gain fat. But, the exercise did not protect them from the effects of high protein on blood sugar control.

The researchers acknowledge that the physiological differences between mice and humans is a limitation of the study but stress that their work may explain why, despite the body of evidence showing that high-protein levels have poor metabolic effects, people consuming high-protein diets or supplements to support their exercise regime are not metabolically unhealthy.

The bottom line? Resistance exercise appears to protect from high-protein induced fat gain, at least in mice. This suggests that metabolically unhealthy, sedentary individuals with a high-protein diet might be better off reducing their protein or adding more resistance exercise.

Seasonal Eating & Metabolism. Recent research from the University of Copenhagen set out to investigate the link between seasonal light and metabolism. For the study, researchers exposed laboratory mice to different hours representing different seasons. Then they measured markers of metabolic health and the circadian rhythms of the mice.

They found that seasonal light impacts energy metabolism by modulating the timing of eating. Mice exposed to winter light hours had a modest reduction in fat mass and liver triglyceride content. Comparing melatonin-proficient and deficient mice, the effect of seasonal light on energy metabolism was largely driven by differences in the balance of food intake and not melatonin.

The study’s senior author stresses that the results are a proof of principle and notes that “further studies in humans may find that altering our exposure to artificial light at night or natural light exposure over the year could be used to improve our metabolic health.”

Extra Point

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Meddling: The Olympic Skating Scandal That Shocked the World. During the 2002 Winter Olympics, the Canadian figure skating pair lost the gold medal to their Russian counterparts in a highly controversial decision. This four-part documentary series explores the resulting scandal and includes present day interviews with the skaters and the judge accused of fixing the results. Meddling is streaming on Peacock.

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The Genius Life. When Max Lugavere’s mother was diagnosed with Parkinson’s disease he began a mission to find the best foods for brain health. In his podcast, he shares his knowledge and interviews experts with the aim of helping listeners optimize their physical and mental wellbeing. He often takes on controversial topics and challenges conventional thinking. (Fair warning: If you’re vegan, some of his ideas may not sit well with you).

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How Rich Donors and Loose Rules Are Transforming College Sports. In this piece for the New York Times, David Fahrenthold and Billy Witz explore how one of the biggest issues in college sports—the rise of big money payments to student athletes from donor collectives—is transforming how players are recruited and “encouraging a form of free agency for those looking to transfer.”