A major review links protein restriction with healthy ageing, but scientists are not telling everyone to eat less. Here is what the evidence means for humans.
Protein is one of the most hyped nutrients in the modern world, valued by fitness enthusiasts and everyday people alike. Maybe some of us are opting to turn yoghurts and protein bars into meals to manage our weight or bulk up our lifestyle, while others are adding extra chicken to our plates based on advice given by doctors, influencers, or our nearest and dearest. Either way, this heightened awareness over protein often has us recalculating our calorie intake around it.
So it may come as a surprise that new research has pointed us in a rather interesting – and contrasting – direction.
A review recently published in Cell Press Blue, which analysed over 350 studies on protein, amino acid restriction and healthy ageing, forwards a possibility that opposes popular belief: consuming less protein could influence healthy ageing, although this has not been proven in humans.
Should we be cutting down on our protein intake instead?
Here is what we know – and how much still needs to be explored.
What Is Protein – And How Much Is Typically Recommended?
Protein is a macronutrient made up of amino acids, which the body uses to break down nutrients, build and repair tissues, and perform whatever else is needed to keep us functioning – which makes it central to our wellbeing.
For healthy adults, the general recommendation is 0.8 grams of protein for every kilogram of body weight per day, though individual needs may vary. Singapore guidance recommends about 1.2 g/kg daily for adults aged 50 and above to support muscle health.
And this is where things get a little more nuanced.
Protein requirements can change with age, physical activity, pregnancy, illness, or other circumstances. For instance, someone undertaking resistance training may have greater nutritional considerations.
However, the story is a little different for those who spend most of the day sitting.
“It’s absolutely crystal clear that there are benefits of protein to muscle growth and exercise response of active individuals,” said Dudley Lamming, one of the review’s authors, in a press release. “But because most people are relatively sedentary, many people are likely consuming more protein than they actually need, which probably has negative health consequences.”
What The New Study Found
The review examined a large body of research on how protein – specifically amino acids methionine, isoleucine, and valine – may influence ageing via the activation of biological pathways involved in growth.
While these pathways are essential, persistent stimulation has been linked to inflammation and metabolic problems in experimental research..
In contrast, protein restriction appears to positively influence several biological systems involved in ageing and metabolism. One particularly interesting mechanism involves FGF21, a hormone involved in regulating energy homeostasis. In animal studies, higher FGF21 levels were associated with greater longevity, and reducing protein consumption helped raise them, and was associated with changes in energy expenditure, body fat and insulin sensitivity in animal studies.
Protein restriction may also change the signalling pathways of mTORC1 and GCN2, potentially altering cellular growth and stress responses, through improving the body’s efficiency in discarding and replacing damaged cellular components. Furthermore, an improvement in mitochondria – known as the powerhouse of the cell, which converts food and oxygen into usable energy – was observed, lowering oxidative stress and boosting energy production. These findings were linked to longer lifespans and less age-related frailty.
The review therefore challenges the common assumption that increasing one’s protein intake is beneficial for everyone.
However, there is a crucial catch.
Caveats on This Study
It should be noted that much of the evidence surrounding protein restriction comes from animal studies. While animals can provide valuable clues about the biology of ageing, findings in fruit flies and rodents do not automatically translate into recommendations for humans.
Furthermore, the review focuses on specific amino acids that should be restricted, rather than protein itself, and there is no single “low-protein diet” that can be applied universally. Protein remains an essential nutrient, and not getting enough of it can still impair physical and mental function.
Importantly, there remains plenty of research that can also prove a protein-rich diet is beneficial. Ultimately, more data and human trials on protein restriction are needed.
Looking Beyond Protein
When it comes to longevity, we need to rely on more than just one specific superfood. A nutritious diet is not about hitting a protein target, but ensuring our whole plate also has enough fruits, vegetables and whole grains to provide us with the energy, fibre and vitamins we need.
And while the amount of protein still matters, so does its source. Those who consume more plant-based proteins are less likely to develop chronic diseases compared to those who eat more red and processed meats.
Moreover, physical activity is one of the strongest pillars of healthy ageing, helping us retain mobility and cognitive function as we enter our golden years. Exercise is also especially relevant to the protein conversation – it gives the body a reason to employ the nutrient in muscle maintenance.
Even beyond food and exercise, adequate sleep, social connections and stress management are vital aspects of our health and quality of life. At the end of the day, the most meaningful lesson in the longevity conversation is not about nutrition labels, but about creating a way of eating and living that your body can thrive on for decades.
Read More
- New Study Reveals Link Between Meat Consumption and Cancer Risks
- Is High Protein Always Better? What Science Actually Says
External References
- Cell Press. (2026, August 2). Eating less protein could slow aging, major review finds. ScienceDaily. Retrieved from: https://www.sciencedaily.com/releases/2026/08/260801042811.htm
- Cleveland Clinic. (2025, June 24). Proteins. Retrieved from: https://my.clevelandclinic.org/health/body/proteins
- French, M. (2026, August 6). Longevity: Eating Less Protein Linked to Healthy Aging in New Studies. Healthline. Retrieved from: https://www.healthline.com/health-news/longevity-less-protein-linked-healthy-aging
- HealthHub. (2025, July 4). Why Protein Is More Important Than You May Think, And 5 Common Protein Myths. Retrieved from: https://www.healthhub.sg/well-being-and-lifestyle/food-diet-and-nutrition/why_protein_is_important
- Knopf, B. A., & Lamming, D. W. (2026). The hallmarks of protein and amino acid restriction in aging and longevity. Cell Press Blue, 1(5). Retrieved from: https://www.cell.com/cell-press-blue/fulltext/S3051-3839(26)00077-0?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS3051383926000770%3Fshowall%3Dtrue
- Mosbergen, D. (2026, August 4). Could Eating Less Protein Help You Age Better and Live Longer? Time. Retrieved from: https://time.com/article/2026/08/03/eat-less-protein-age-better-live-longer/
- Sakay, Y. N. (2026, August 4). Why reducing protein intake could promote healthy aging, according to new research. Medical News Today. Retrieved from: https://www.medicalnewstoday.com/articles/why-reducing-protein-intake-could-promote-healthy-aging-new-research
- HealthHub (2023, March 13). Older Adults Need More Protein. Retrieved from: https://www.healthhub.sg/well-being-and-lifestyle/active-ageing/seniors-need-more-protein
