Lately, it seems like every popular eating plan is a high-protein diet.
After all, Paleo, Medifast, and the Dukan Diet all blow through the current recommendations on protein intake. And even people who aren’t on a so-called diet are generally trying to eat more lean meats, nuts, seeds, and low-fat dairy in an effort to boost their metabolism, build muscle, and lose weight. Meanwhile, some experts say that Americans are getting more than enough protein, even before they start trying to follow a high-protein diet.
Much of the confusion comes down to what the current recommendations on protein actually are. The most common target people typically hear is 0.8 grams of protein per kilogram of body weight, and that works out to 0.36 grams of protein per pound of body weight or, in a 165-pound adult, about 60 grams of protein per day – about the equivalent of 3 cups of Greek yogurt, or one whole chicken breast.
But 0.8 is just the recommended daily allowance, or RDA, for protein intake for the average healthy adult, and contrary to popular opinion, the RDA isn’t exactly recommending how much you should eat per day, says Donald K. Layman, Ph.D., professor emeritus of food science and human nutrition at the University of Illinois. “The RDA of protein is defined as the minimum amount you need. It doesn’t mean it’s a healthy optimum.”
Meanwhile, the current dietary guidelines say we should get between 10 to 35 percent of our daily calories from protein. If you follow the 0.8 rule, that should put you at right about 10 percent, and Harvard University estimates that most people currently get about 16 percent of their calories from protein. And according to research published in The American Journal of Clinical Nutrition, even the top 5 percent of protein consumers don’t approach the 35-percent mark.
Eat More Protein, Build More Muscle
But many people may need to inch their way a bit closer to 35 percent with a high-protein diet. Namely, weight-loss warriors, exercisers and both children, and older adults.
For instance, a 2015 review published in Applied Physiology, Nutrition, and Metabolism shows that people get about 25 percent of their calories from protein. If you’re eating 2,000 calories a day, that’s about 125 grams daily. Each gram of protein contains four calories.
Meanwhile, the American College of Sports Medicine recommends that to increase muscle mass in combination with physical activity, you need to follow a high-protein diet containing 1.2 and 1.7 grams of protein per kilogram of body weight per day, or 0.5 to 0.8 grams per pound of body weight. That equates to about 80 to 135 grams in a 165-pound adult. Oliver C. Witard, Ph.D., exercise metabolism researcher at the University of Stirling in Scotland, advises consuming even more, namely those trying to hit new PRs.
“For athletes seeking optimum performance, a recommendation of 1.6 to 2.0 grams of protein per kilogram of body weight may be beneficial,” he notes. Contrary to some previous concerns over the risks of excessive protein intake, 2.0 grams per kilogram is not “too high” and is not harmful, he adds. Layman agrees. “A lot of people out there will say that eating too much protein is bad for the kidneys or bones, but those are myths,” he says. “The only evidence that protein can be harmful to the kidneys is in people who already have kidney issues. For healthy individuals, most studies show that intakes [of] up to 3 grams of protein per kilogram of body weight [are] OK. And that’s a ridiculously high amount.”
Gaining and preserving muscle mass through a high-protein diet is vital not just to bodybuilders and athletes, though. It’s also important to growing children as well as older adults who are at risk for age-related muscle loss, Witard says. In one American Journal of Physiology – Endocrinology and Metabolism study of healthy adults ages 52 to 75, those who consumed 1.5 grams of protein per kilogram of body weight built and preserved more muscle than those who ate according to the 0.8 minimum. “As we get older, our bodies become less efficient in using protein,” Layman says. “We need more protein to encourage the same muscle health.”
When You Get Your Protein Also Matters
While the total amount of protein you eat in a day certainly impacts your muscle as well as overall health, people also need to pay attention to when they get that protein. “There is some evidence that spreading your daily protein intake across all meals would be more beneficial [than having] a low-protein breakfast, some protein at lunch and excessive protein at dinner, as currently followed by most people,” says Rajavel Elango, Ph.D., a researcher in the School of Population and Public Health at the University of British Columbia and co-author of the Applied Physiology, Nutrition, and Metabolism study.
After all, since protein is known to promote satiety, prevent overeating and help control blood sugar levels, people stand to benefit from it the most if they consume it regularly. Plus, since, in response to protein ingestion, the body only builds muscle for about two hours, spreading your protein intake throughout the day can multiply the time your body spends building, not breaking down, muscle, Layman says. He recommends shooting for between 30 and 40 grams of protein at every meal – you’ll get that from a 3-ounce serving of salmon and cup of edamame.
Written for USNews.com