We are forever striving to increase the amount of protein in our diets. We're sprinkling protein powder into yogurt, oatmeal, and smoothies, and buying snack bars and even pasta with extra grams of the stuff. But do we need to?
For most of us, the answer is no. Dr David Katz, director of the Yale University Prevention Research Center, believes the protein craze is for the most part just that—another craze, like low-fat in the 1980s and low-carb in the early 2000s. "All the focus on macronutrients has been a massive boondoggle—we cut fat and got fatter and sicker; we cut carbs and got fatter and sicker," he says. "We need to stop focusing on macronutrients and focus on wholesome foods and healthy combinations and let the nutrients take care of themselves."
Besides, we already get plenty of protein. The Australian Dietary Guidelines recommends getting between 15 percent and 35 percent of your daily calories from protein. Just 10 percent—that's around 46 g of protein per day for women—would be enough to meet the Recommended Daily Allowance (RDA) and prevent deficiencies, and CDC data shows that we tend to get closer to 16 percent.
And yet, Katz says, certain types of people can benefit from greater protein intake. After all, we all have different bodies with individual nutritional needs, so no single protein guideline will fit all.
The best protein sources, he says, are eggs, fish, poultry, and small amounts of lean, grass-fed meats (a few four-ounce servings a week), along with beans, soy, and lentils combined with nuts and seeds or rice and grains. In other words, don't be tempted to pile on the bacon. Although meat is certainly a high-quality protein—meaning it has the right distribution of amino acids for our body's needs—it brings along other "passengers" that are harmful, namely saturated fat, high total fat, cholesterol, and, depending how we cook it, possibly carcinogens.
Here are the four types of people Katz says may benefit from higher protein intake, which means getting a bigger proportion of calories from protein—not just piling extra protein onto your regular diet.
If you're doing a lot of resistance training or taxing endurance exercise, you're tearing down muscle tissue that needs to be repaired and rebuilt. "Protein is a source of essential amino acids that are the building blocks of the body's own proteins—and we can't make them. We get them from food or we don't get them at all," Katz explains. "And that's clearly detrimental."
People who are prone to weight gain
"There's a reasonable amount of evidence to suggest that higher protein, depending on where the protein comes from, may help with low-calorie compliance by providing satiety," says Dr Tom Rifai, regional medical director of metabolic health and weight management for the Henry Ford Health System in Detroit. That's because protein takes longer to digest, leaving us feeling fuller. It also stabilizes blood sugar, which has been shown to lower our desire to eat—helpful when trying to shed pounds.
"During weight loss, you want more protein to prevent hunger, enhance satiety, and minimize muscle loss, as long as there's some degree of physical activity." Legumes are a particularly great source of protein, as a 2014 study in the journal Obesity found that eating a daily serving of beans, chickpeas, lentils, or peas increases fullness, potentially improving weight management and weight loss.
People with a very sugary, carby, crappy diet
Anyone eating the typical American diet (think: bread, pasta, and snack packs) can benefit from shifting toward more high-quality protein, like egg whites, fish, and lean meat. "If you're getting a higher percentage of calories from protein, you're getting less of the other stuff, like added sugar and carbohydrates," says Katz.
In other words: "More tuna, fewer doughnuts." In a randomized trial known as the Optimal Macronutrient Intake Trial to Prevent Heart Disease (OmniHeart), people who replaced some carbohydrate with healthy protein (or healthy fat) saw lower blood pressure and lower levels of harmful LDL cholesterol than people on a higher-carbohydrate diet that was otherwise healthy.
People in middle age
Getting a little extra protein may be helpful after age 50 to counteract the inevitable muscle loss that comes with aging. "Older adults at risk of sarcopenia, the gradual loss of lean muscle mass, would benefit from more high-quality protein in their diet," says Katz. In a 2015 study from the University of Arkansas for Medical Sciences, adults ages 52 to 75 who doubled the recommended daily allowance were better at building muscle—and keeping muscle—after just four days. For people in this age group, who may already have high cholesterol or other cardiovascular risk factors, it's a good idea to grab extra protein from beans, seeds, whole grains, nuts, and fish instead of red meat, dairy products, and eggs, which are high in saturated fats.