The recommended intake (RDA) of protein, the amount needed to meet the nutritional needs of almost all healthy people, is 0.8 g per kilogram (kg) of body weight.
For example, if you weigh 150 pounds, your body weight in kilograms is 68. Multiply 68 by 0.8 to get your daily protein goal of 54 grams.
But the RDA isn’t one-size-fits-all, and many factors affect how much protein you need, including your age, body size, muscle mass, whether you’re active, and whether you have any illnesses, says Stephanie McGill, RD, a Seattle-based sports dietitian.
By definition, the RDA is intended to meet the needs of 97 to 98 percent of healthy adults in the United States.
This means that the RDA may not be enough for some healthy adults.
There are also people with specific health conditions who may need different amounts of protein: older people may need up to 1.2g of protein per kg of body weight to prevent age-related muscle loss (sarcopenia).
People who are sick or recovering from surgery should also take in up to 1.5g of protein per kg of body weight per day, as their bodies need more protein to function under stress.
Gabriel Lyon, M.D., a functional medicine physician and founder of the Institute for Muscle-Centric Medicine in New York City, says it may be best to use the RDA as a starting point rather than a fixed goal. “All adults should start with a basal level of protein, regardless of activity level or calorie intake,” says Dr. Lyon.
