July 29, 2026, 7:53 am | Read time: 6 minutes
Are the official recommendations for protein and exercise really enough to stay healthy and fit for as long as possible? Chris Macdonald, a behavioral researcher and director of the Better Protein Institute at the University of Cambridge, doubts it. In a recent perspective paper, he argues that many guidelines primarily aim to prevent deficiencies rather than to maintain physical and mental performance in old age as best as possible.
More Exercise and More Protein for a Healthier Life
The perspective paper questions two established recommendations: the minimum amount of exercise and the recommended protein intake.1 According to the renowned scientist, current studies suggest that both more exercise and higher protein intake could improve the chances of a long, healthy life.
The author concludes that many people could benefit from a higher protein intake than is currently officially recommended. The studies evaluated link a protein-rich diet with increased muscle mass and greater strength gains, among other things. They also point to better physical function in old age and benefits for athletes and pregnant women.
How the Study Was Conducted
The publication is not an original study with participants but a so-called perspective paper published in the journal “Frontiers in Nutrition.” Author Chris Macdonald evaluated previously published research on exercise and protein intake and contextualized their results. The goal was to examine whether current recommendations still align with today’s knowledge or merely cover minimum requirements.
He drew on meta-analyses, reviews, randomized studies, and observational studies, among others. The focus was on two topics: physical activity—especially endurance and strength training—and the protein needs of various population groups, including older adults, athletes, and pregnant women.
Why the Author Recommends More Protein
Regarding protein intake, the author argues that many people—including older adults, endurance athletes, and pregnant women—could benefit from amounts well above the current minimum standards. Macdonald suggests 0.7 grams per pound (about 1.5 grams of protein per kilogram of body weight) as a target for healthy adults. He emphasizes quality: Protein should be consumed with natural nutrients rather than through highly processed products.
For comparison: The German Nutrition Society currently recommends 0.8 grams of protein per kilogram of body weight per day.2 The current recommendation in the United Kingdom is also 0.34 grams per pound of body weight, which translates to 0.75 grams of protein per kilogram of body weight.
Newer studies also suggest that older adults should consume at least 25 grams of protein per meal. For pregnant women, there are indications of a higher requirement of around 0.6 grams per pound of body weight daily (about 1.3 grams per kilogram) to support fetal growth and reduce the risk of certain complications. However, the author emphasizes that these figures are based on the research literature he evaluated and do not reflect current official recommendations.
It’s important to know: The figures per pound of body weight come from the British and international studies Macdonald evaluated. He adopts the unit commonly used in the Anglo-American region.
Macdonald also has an opinion on exercise. Just about 15 minutes of exercise daily could reduce mortality risk. People who combine endurance and strength training could benefit even more. Additionally, data from the UK Biobank suggest that intense exercise per minute might be more effective than moderately strenuous activity.
Is 1.5 Grams of Protein a Lot?
For context: In sports science, this amount is by no means considered extreme. Currently, the International Society of Sports Nutrition recommends athletes consume 1.4 to 2.0 grams of protein per kilogram of body weight, adjusted to training status and goals.3
An analysis of 49 controlled studies with nearly 1,900 participants concluded in 2018 in the journal “British Journal of Sports Medicine” that more protein builds additional muscle in combination with strength training. This worked up to a protein intake of about 1.6 grams per kilogram—beyond that, it no longer had an effect. However, this value is not entirely certain, as the statistical range extends from 1.0 to 2.2 grams.4
Two numbers from the analysis are particularly revealing. Most of the muscle gain was due to the training itself, about 1.1 kilograms in roughly three months. The additional protein contributed only 0.3 kilograms. Secondly, for older participants, the extra protein had virtually no effect.
The second point contradicts other research. These studies justify a higher need in old age precisely because muscles respond less to protein over the years—and therefore more is needed. So, the data is not clear-cut.
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How Much Protein People Over 60 Should Eat
What This Means in Practice
Macdonald mostly refers to British guidelines and recommendations from the National Health Service (NHS) and the UK Department of Health in his analysis. However, his demands are fundamentally broader. They go beyond the point that British protein guidelines have remained largely unchanged since 1991. The author advocates that governments in general should align their recommendations on exercise and protein intake more with optimal health outcomes rather than mere minimum requirements.
Applied to Germany, Macdonald’s initiative would primarily mean a departure from minimum recommendations. In his view, dietary recommendations and exercise guidelines should not primarily aim to prevent deficiencies and diseases. Instead, they should focus more on maintaining physical performance, muscle strength, independence, and mental fitness into old age.
Assessment of the Paper
The strengths of the perspective paper include the broad evaluation of current research in the areas of exercise, nutrition, and healthy aging. The author bases his argument on numerous reviews, meta-analyses, and clinical studies. At the same time, Macdonald himself points out important limitations. Nutrition and lifestyle research often relies on self-reports and can be influenced by confounding factors such as smoking habits, alcohol consumption, education, or other health behaviors.
Moreover, the data on many questions regarding optimal protein intake is still limited, so larger studies are needed. It is also important to note that this is not a clinical study but a perspective paper. The proposed adjustments to the guidelines therefore reflect the author’s assessment of the existing literature and were not tested in an independent study.