The More Protein, the Better?

New York Times

09-04-2025

We're in a protein craze, and it's hard to ignore.
Walk into any grocery store and you'll find rows of protein-fortified energy bars, breakfast cereals, baked goods, snacks, even sports drinks. And on social media, influencers — many with medical or scientific degrees in their bios — claim that most people are woefully deficient.
'Ladies, you're NOT eating enough protein,' Dr. Elie Jarrouge, a doctor in Houston wrote to his nearly 80,000 followers on Instagram in February. Dr. Gabrielle Lyon, another Houston-based physician, said in a recent video on TikTok that the federal recommendations for protein are 'totally wrong.'
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 U.S. adults, 71 percent said they were trying to consume more protein — up from 59 percent in 2022.
So, are the federal recommendations wrong? Would most of us 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 of them agreed that we need more research on the topic, but the science we do have clarifies some of the confusion. Here is a fact-check of six big protein claims we've seen.
The claim: The federal recommendation is wrong.
Nutrition experts in the United States recommend that most healthy adults eat at least 0.8 grams of protein per kilogram of body weight (or 0.36 grams per pound) every day. For a 150-pound adult, this translates to 54 grams per day — or the amount in an 8.5-ounce chicken breast.
Some studies, which Dr. Attia and Dr. Lyon have cited, suggest this amount should be higher — by about 25 to 50 percent, or 1 to 1.2 grams per kilogram of body weight. But scientists don't agree that those studies are better than the ones used to make the federal recommendation.
The best (if limited) evidence we have suggests that the current level is adequate for most people's basic needs, said 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, Dr. Campbell 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. Campbell, like many of the experts we spoke with, has received research funding from food industry groups. This is common among protein scientists because there is little federal funding for these types of studies.)
Dr. Attia declined multiple requests for comment. In an interview, Dr. Lyon criticized the recommendation, in part because she said it was based only on data from 25-year-old men. That's not true; it was based on data from men and women ages 18 to 99.
The claim: Most Americans aren't getting enough protein.
According to the latest data, the average man in the United States is overshooting the federal protein recommendation by more than 55 percent and the average woman by more than 35 percent.
If most people weren't consuming enough protein, there would be widespread signs of malnutrition, and there are not, said 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.
Teen girls and women are more likely to restrict their eating, Dr. Rodriguez said, and women tend to consume less meat than men. Older adults also usually eat less overall and may struggle to afford, cook or chew protein-rich foods, she added.
Protein deficiency isn't a widespread problem, experts said. But people in these groups may need to be more attuned to how much they're getting.
The claim: You need more protein to build muscle.
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, Dr. Lyon and other protein proponents suggest similar targets, along with exercise.
If you're strength training, experts said that you'll probably want to consume more protein than the federal recommendation. But tripling it 'is far more than most people require,' said 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 program 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 David Church, an assistant professor of geriatrics at the University of Arkansas for Medical Sciences. Beyond that amount, he added, the effects of protein on muscle gain 'kind of plateaus.'
Some small studies, Dr. Church said, do suggest that certain athletes — like those doing rigorous strength and endurance training, or those recovering from injuries or restricting their calories — may benefit from consuming up to three times the federal recommendation. But more research is needed, and these scenarios don't apply to most people, he added.
In an email, Dr. Sims emphasized that her recommendations were mainly for serious female athletes who are typically training for a specific sport or competition.
The claim: Older adults need more protein.
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 ages 65 to 79, for example, those who consumed about 50 percent more protein than the federal recommendation were less frail than those who consumed less.
But other studies in older adults, including randomized 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 percent 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 over 65 to consume at least 25 percent more protein than the U.S. guidelines recommend. And, they add, older people may benefit from eating even more if they are healing from injury or recovering from surgery or hospitalization — a recommendation Dr. van Loon agreed with.
The claim: High protein diets can help with weight loss.
Many posts on social media — many of them geared toward 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 haven't always found that people lose more weight on high-protein diets compared with other weight loss diets, said Bettina Mittendorfer, a professor of nutrition and exercise physiology at the University of Missouri School of Medicine.
Still, research suggests that if you're actively trying to lose weight, increasing your protein may help you lose more fat mass and retain more lean mass, which includes muscle. In a review published in 2024, scientists concluded that consuming at least 25 percent 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's important to get adequate protein, Dr. van Loon said. Strength training at least twice a week is also key to preserving muscle during weight loss, he added.
The claim: The more protein the better.
If you spend time online, you may see posts urging you to eat significantly more protein and that there's 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 fruits, vegetables and whole grains — which most of us need more of, Dr. 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 like beans, tofu, nuts, whole grains, fish or chicken, which are more healthful options, he said.
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 United States are estimated to have chronic kidney disease, and up to nine out of 10 don't 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 villainized, yet scientists found that the nutrients themselves weren't bad; the issue was more about overeating certain foods they were in.
As with any nutrient, she added, you shouldn't have too much or too little. There's a 'Goldilocks zone' that meets your body's needs without causing problems, she said. The same is true for protein.