{"id":588223,"date":"2026-08-18T08:37:00","date_gmt":"2026-08-18T08:37:00","guid":{"rendered":"https:\/\/www.newsbeep.com\/il\/588223\/"},"modified":"2026-08-18T08:37:00","modified_gmt":"2026-08-18T08:37:00","slug":"im-a-longevity-expert-high-protein-diets-could-be-doing-us-more-harm-than-good","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/il\/588223\/","title":{"rendered":"I\u2019m a longevity expert. High protein diets could be doing us more harm than good"},"content":{"rendered":"

It\u2019s the miracle macronutrient, capable of helping build muscle<\/a>, lose fat, boost bone strength <\/a>and bolster the immune system<\/a>, among other benefits. The overarching message: more protein is better. <\/p>\n

But new research says otherwise. In fact, it suggests that eating too much protein<\/a> could speed up the ageing process and contribute to increased diabetes risk and larger waistlines. Restricting daily protein totals, on the other hand, could deliver better body composition and metabolic health. <\/p>\n

There is, however, more nuance to it than that. Professor Valter Longo<\/a>, co-lead author of this new study<\/a>, highlights how protein is composed of building blocks called amino acids, and different protein sources deliver different amino acids in varying amounts. It is not just how much protein you eat, but also where it\u2019s coming from<\/a>, that could determine your future health. <\/p>\n

The secret ingredient for a long and strong life<\/p>\n

\u201cIf you think about mice and rats and a lot of species, we\u2019ve known for many years that one of the ways to make them live longer is to restrict protein,\u201d says Professor Longo, author of book The Longevity Diet.<\/p>\n

\u201cWe also know that populations such as southern Italians and probably also the Japanese [both areas associated with longevity and low protein diets] are relatively frail compared to central and northern European countries.<\/p>\n

\u201cThis paper tried to solve that problem. Is it possible to eat a low-protein diet but prevent strength decreases and frailty?\u201d <\/p>\n

It turned out that adding just a little bit of methionine to a low-protein diet, similar to the Okinawan or Mediterranean diet, makes a big difference<\/p>\n

Professor Valter Longo<\/p>\n

Working with mice, Professor Longo and his team made one small tweak to a low-protein diet to achieve this: they increased the intake of an essential amino acid \u2013 one that can\u2019t be produced by the body \u2013 called methionine. <\/p>\n

\u201cIt turned out that adding just a little bit of methionine to a low-protein diet, similar to the Okinawan or Mediterranean diet, makes a big difference,\u201d Professor Longo explains. \u201cIt can keep strength, maximise longevity and cause fat loss, but not lean body mass [muscle] loss, while allowing for high calorie consumption.\u201d<\/p>\n

Methionine can be found in everything from animal proteins to nuts, seeds, whole grains and legumes, but the amounts vary greatly. Animal proteins tend to contain larger amounts, while some plant-based protein sources have far lower totals. <\/p>\n

For the best health effects, Professor Longo recommends treating methionine like you are Goldilocks. Too little leads to frailty; too much leads to \u201cweight gain and accelerated ageing\u201d. <\/p>\n

He says \u201cthe ideal protective balance\u201d can be achieved with a low-protein diet in which plant-based protein sources outweigh animal-based ones by a rough two-to-one ratio. The animal sources, he adds, should be mostly fish, with few red and processed meats. <\/p>\n

Read more: I tried the 12-minute daily workout Helen Mirren\u2019s used for her \u2018whole life\u2019 \u2013 here\u2019s why it\u2019s stood the test of time<\/a><\/p>\n

\"ProfessorProfessor Valter Longo prescribes a low protein diet with largely plant-based protein sources for better longevity (Getty\/iStock)<\/p>\n

Does this advice apply to humans?<\/p>\n

As part of their study, Professor Longo and his team asked Harvard Department of Nutrition chair Professor Frank Hu to analyse data from more than 200,000 men and women. <\/p>\n

The results found that \u201cthose with the highest animal protein intake tended to have a healthier lifestyle, but had approximately double the prevalence of type 2 diabetes compared with those in the lowest intake group\u201d.<\/p>\n

\u201cThis could explain why so many people have relatively healthy diets but they get diabetes or they become overweight,\u201d Professor Longo says. \u201c…These people with a high animal protein diet had a much higher risk of developing diabetes and a much higher proportion of overweight and obesity.\u201d<\/p>\n

\u201cThese findings indicate that mostly plant-based low-amino-acid diets have the most potent effects on healthspan, but require moderate methionine intake to minimise frailty,\u201d the researchers summarise. <\/p>\n

Read more: I did goblet squats every day for a month and the results surprised me<\/a><\/p>\n

\"DietsDiets low in protein and containing moderate levels of the amino acid methionine can help you stay stronger for longer, research suggests (Getty\/iStock)<\/p>\n

But what about if you are an active person who wants to build muscle?<\/p>\n

It is generally accepted that active people need more protein in their diet to support their exercise endeavours. Activities such as lifting weights, jumping and sprinting trigger positive changes in the body, and the body uses amino acids from proteins to action these adaptations \u2013 larger muscles, stronger bones, more robust joints. <\/p>\n

A prescription you will often hear gym-goers cite is to consume 2g of protein per kg of body weight per day; a total that likely stems from papers such as this 2016 investigation<\/a>, which concluded that daily protein intakes as high as 3.4g per kilogramme of body weight may deliver benefits to body composition \u201cin conjunction with a heavy resistance-training program\u201d. <\/p>\n

But there is a counterargument. How much of this considerable daily target \u2013 306g for a 90kg man, or roughly 50 eggs \u2013 is actually being put to good use?<\/p>\n

Another example of research reinforcing higher protein intakes is this 2019 review.<\/a> It supports protein recommendations of 1.6-2.4g per kg of body weight per day for losing fat, maintaining muscle and supporting performance in athletes.<\/p>\n

\"ThoseThose regularly exercising are thought to need more protein \u2013 but often this is the recommendation for top athletes only (Getty\/iStock)<\/p>\n

\u201cIn athletes\u201d is a key phrase here. Due to their intense training and performance goals, athletes\u2019 dietary needs are going to be different to those of most people. <\/p>\n

More and more, I\u2019ve noticed marketing campaigns targeting everyday folks with prescriptions intended for top-level athletes: unwieldy protein quotas, immaculate sleep schedules, supplement-fuelled morning routines. A lot of the time, these are surplus to requirements, and often parroted to sell pricey fitness products.<\/p>\n

Supporting this viewpoint, a 2017 systematic review and meta-analysis<\/a> concluded that, while protein supplementation could help healthy adults gain muscle strength and size from strength training, intakes beyond roughly 1.6g per kilogramme of body weight per day \u201cdo not further contribute to muscle growth\u201d.<\/p>\n

This is the ballpark figure I have come to aim for, and it has served me well over the years. I have been able to gain muscle, maintain a body composition I am comfortable with and hit several running and strength-based performance goals along the way. But Professor Longo recommends a lower intake. <\/p>\n

Read more: What your walking speed reveals about your risk of heart disease and dementia<\/a><\/p>\n

\"TheThe traditional Mediterranean diet is a good model for healthy eating, advising people to eat most of their animal protein in the form of fish (Alamy\/PA)<\/p>\n

How much protein should you eat per day, according to a longevity expert<\/p>\n

\u201cWhat you eat should be personalised,\u201d Professor Longo tells me. \u201cThis is why I prefer to talk about proportions rather than exact amounts. <\/p>\n

\u201cYou could start with 0.8 [grams of protein per kilogramme of body weight per day]. That\u2019s a minimum approved by every medical association in the world. Start with 0.8g\/kg and have a two-to-one ratio of plant to animal proteins.\u201d<\/p>\n

However, he adds, if you are strength training regularly and find you are losing muscle by following this approach, you might need to tweak it. <\/p>\n

\u201cWe just reviewed a lot of papers, and it turns out that excess protein is not going to help you that much [regarding muscle growth], but your training is going to help you a lot,\u201d Professor Longo explains. \u201cBut if you\u2019re doing resistance training and you\u2019re still losing muscle, your amino acid [intake] may be insufficient and you might have to raise it a bit.<\/p>\n

\u201cMaybe just raise it 10 or 20 per cent \u2013 none of this 2g\/kg that people have been talking about. If you\u2019re losing muscle mass, it probably just means moving from 0.8g\/kg to 1.1g\/kg and that should take care of the problem.\u201d<\/p>\n

Read more: I tried \u2018Spider-Man\u2019 Tom Holland\u2019s 20-minute bodyweight workout \u2013 it\u2019s a superhero crash course<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"It\u2019s the miracle macronutrient, capable of helping build muscle, lose fat, boost bone strength and bolster the immune…\n","protected":false},"author":2,"featured_media":588224,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36],"tags":[163,85,46,543,266085],"class_list":["post-588223","post","type-post","status-publish","format-standard","has-post-thumbnail","category-nutrition","tag-health","tag-il","tag-israel","tag-nutrition","tag-pa-feature-health-omega3-food"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/588223","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=588223"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/588223\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/588224"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=588223"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=588223"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=588223"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}