Are you getting enough protein? Is there such a thing as too much?

Straits Times

13-05-2025

Protein is important, but focusing too much on it can come with downsides, such as having less room for other healthy foods such as fruit and vegetables. PHOTO ILLUSTRATION: MORGANE FADANELLI/NYTIMES
Are you getting enough protein? Is there such a thing as too much?
NEW YORK – People are in a protein craze, and it is hard to ignore.
Walk into any grocery store, and you will find rows of protein-fortified energy bars, breakfast cereals, baked goods, snacks and even sports drinks. And on social media, influencers – many with medical or scientific degrees in their bios – claim that most people are woefully deficient.
One of the most well-known protein proponents is Dr Peter Attia, a physician, podcaster and author who advises and invests in various protein-related food companies. In his best-selling book, Outlive, he says that the federal recommendations for protein are 'a joke', suggesting that most healthy and active people should consume nearly three times as much.
In a 2024 survey of 3,000 American adults, 71 per cent said they were trying to consume more protein – up from 59 per cent in 2022.
So, are the federal recommendations wrong? Would most people benefit from eating more protein? Or is the obsession just another passing health fad?
The New York Times reviewed dozens of studies and interviewed 12 nutrition scientists, many of whom have been studying protein for decades. All agreed that more research on the topic is needed, but the science now does clarify some of the confusion.
Here is a fact-check of six big protein claims.
The claim: The federal recommendation is wrong
Scientists have debated whether it should be a little higher, but the current level seems adequate for most people.
Nutrition experts in the United States recommend that most healthy adults eat at least 0.8g of protein per kg of body weight every day. For a 68kg adult, this translates to 54g a day – or the amount in about 240g of chicken breast.
Some studies suggest this amount should be higher — by about 25 to 50 per cent, or 1 to 1.2g per kg of body weight. But scientists do not agree that those studies are better than the ones used to make the federal recommendation.
The best – if limited – evidence now suggests that the current level is adequate for most people's basic needs, said Dr Wayne W. Campbell, a professor of nutrition science at Purdue University.
The federal recommendation was intended to prevent protein deficiency and to maintain lean tissues, like muscle, in most people, he added . That level is not necessarily optimal for everyone.
Many people – including those who are strength training or losing weight – may benefit from consuming more, he said.
Dr Attia declined multiple requests for comment.
The claim: Most Americans are not getting enough protein
Research suggests this is false. According to the latest data, the average man in the US is overshooting the federal protein recommendation by more than 55 per cent and the average woman by more than 35 per cent.
If most people were not consuming enough protein, there would be widespread signs of malnutrition, and there are not, said Dr Nancy Rodriguez, a professor emerita of nutritional sciences at the University of Connecticut.
People who follow a balanced diet, like one recommended by the Dietary Guidelines for Americans, are probably 'getting plenty of protein', Dr Campbell added – even vegetarians.
That said, not everyone follows a balanced diet, and some people get less than what is recommended, which could put them at risk for deficiency. Teen girls, women and older adults, for instance, are particularly at risk of falling short of the federal recommendation.
The claim: You need more protein to build muscle
Research backs this up.
Dr Stacy Sims, an exercise physiologist and nutrition scientist who offers advice to active women online, recommends consuming up to triple the federal recommendation. Dr Attia and other protein proponents suggest similar targets, along with exercise.
If you are strength training, experts say you will probably want to consume more protein than the federal recommendation. But tripling it 'is far more than most people require', said Dr Luc van Loon, a professor of physiology of exercise and nutrition at Maastricht University in the Netherlands.
In one well-designed trial of 50 middle-aged participants who followed a rigorous strength training programme for 10 weeks, half consumed about 1.5 times the federal recommendation, and the other half consumed about twice as much. After the training period, both groups were stronger and had gained lean mass, with no difference in results between them.
For most people who want to build muscle, consuming around 1.5 to two times the federal recommendation is plenty, said assistant professor of geriatrics David Church at the University of Arkansas for Medical Sciences. Beyond that amount, he added, the effect of protein on muscle gain 'kind of plateaus'.
The claim: Older adults need more protein
Some research backs this up, but more studies are needed.
There is some evidence that consuming more protein as you get older can reduce the risk of age-related muscle loss, but these findings have been mixed.
In a three-year study of nearly 25,000 women aged 65 to 79, for example, those who consumed about 50 per cent more protein than the federal recommendation were less frail than those who consumed less.
But other studies in older adults, including randomised controlled trials, have not consistently shown a benefit to consuming more protein.
In a trial published in 2018, researchers provided 92 older men with diets that either matched the federal recommendation or contained 63 per cent more protein. After six months, the researchers found no differences in lean mass, muscle strength, walking speed, fatigue or well-being between groups.
Despite the mixed evidence, nutrition experts in Europe encourage all people older than 65 to consume at least 25 per cent more protein than the US guidelines recommend. And, they add, older people may benefit from eating even more if they are healing from injury or recovering from surgery or hospitalisation – a recommendation Dr van Loon agreed with.
The claim: High-protein diets can help with weight loss
Research suggests this is partly true.
Many posts on social media – several of them geared towards women – promote high-protein diets for weight loss.
Some short-term trials in women and men have shown that eating 1.5 to two times the federal recommendation helped people lose more weight than lower-protein diets did. Research also suggests that protein can reduce hunger hormone levels and be more satiating than carbohydrates or fats.
But longer-term studies have not always found that people lose more weight on high-protein diets compared with other weight-loss diets, said Dr Bettina Mittendorfer, a professor of nutrition and exercise physiology at the University of Missouri School of Medicine.
Still, research suggests that if you are actively trying to lose weight, increasing your protein may help you lose more as fat and less as lean mass, which includes muscle. In a review published in 2024, scientists concluded that consuming at least 25 per cent more protein than the recommended amount may help preserve muscle during weight loss.
For people consuming fewer calories, whether because they are dieting or taking a medication like Wegovy or Ozempic, it is important to get adequate protein, Dr van Loon said. Strength training at least twice a week is also crucial for preserving muscle during weight loss, he added.
The claim: The more protein, the better
Experts have concerns about this approach.
If you spend time online, you may see posts urging you to eat significantly more protein and saying that there is no harm in doing so.
But focusing too much on protein can come with some downsides, experts said. It might, for example, leave less room for other healthy foods, like fruit, vegetables and whole grains – which most people n eed more of, Prof Church said.
It could also prompt you to eat more animal products, which are linked to higher risks of cardiovascular disease and earlier death, said Dr Frank B. Hu, a professor of nutrition and epidemiology at the Harvard T.H. Chan School of Public Health.
Or you might rely on processed sources of protein, like powders or bars, instead of whole-food sources of protein such as beans, tofu, nuts, whole grains, fish or chicken, which are more healthful options, he added.
Too much protein may also strain the kidneys in those with chronic kidney disease, Dr Campbell said. More than one in seven adults in the US are estimated to have chronic kidney disease, and up to nine out of 10 do not know that they have it.
'That gives me pause about the more-is-better approach,' Dr Campbell said.
Dr Mittendorfer sees echoes of past nutrition trends in today's protein craze. 'There are these waves in public opinion,' she said. Fats and carbohydrates were once villainised, yet scientists found that the nutrients themselves were not bad; the issue was more about overeating certain foods they were in.
As with any nutrient, she added, you should not have too much or too little. There is a 'Goldilocks zone' that meets your body's needs without causing problems, she said. The same is true for protein. NYTIMES
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