In a number of studies, high-protein interventions did not help maintain muscle mass in adults aged 65 or older who already consumed adequate amounts of protein at baseline. However, other studies, including a long-term study led by Tufts researchers, found higher protein intake across adulthood was associated with significantly lower risk of losing physical function with age, particularly in women.

While the U.S. RDA for protein is 0.8 g/kg/d (0.36 g/lb) for adults of all ages, some international expert groups recommend a protein intake of 1.0 to 1.2 g/kg/d for adults over 65 years old. The participants in the Tufts’ study were averaging protein intake of 1.0 g/kg/d, indicating most older adults in the U.S. don’t necessarily need to change their eating habits to meet this higher intake goal.

Weight Management

If you are cutting calories to lose weight, be careful to keep your intake of protein foods at the recommended level. 

“When people cut calories across the board, they generally cut protein intake along with carbohydrates and fats,” says Fielding. “If the body is not getting enough dietary amino acids to build all the proteins it needs, it will break down muscle tissue to get to the amino acids stored there. These dieters will lose body fat, but also lean mass (muscle).” 

Making sure a higher percentage of calories on a low-calorie diet comes from protein can help.

This article originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy.