To get your personal protein "RDA," multiple the number 0.36 by your weight in pounds. (For a sedentary 150-pound woman, that would be 54 grams.) Double it if you're very active or aiming for "optimal protein," which can help you maintain muscle as you age and support weight loss.
American women already eat about 68 grams a day, according to the latest data from the National Health and Nutrition Examination Survey. "There's no reason to go out of your way to get protein," says Dariush Mozaffarian, MD, dean of the Tufts Friedman School of Nutrition Science & Policy. "Just eat a variety of fish, nuts, beans, seeds, and dairy, including yogurt." However, increasing your protein well above the RDA may make sense if ...
That means getting at least 35 to 40 minutes of moderate exercise four or five days a week, including resistance training two or more times a week. Consider eating 1.2 to 2 grams of dietary protein per kilogram (or about 0.5 to 0.9 grams per pound) of body weight each day, says Nancy Rodriguez, PhD, professor of nutritional sciences at the University of Connecticut. That amount is best for rebuilding muscle tissue, especially if you do a lot of high-intensity workouts, research suggests.
You're trying to lose weight
Protein takes longer to digest than carbs, helping you feel full, and also pushes your body to secrete the gut hormone peptide YY, which reduces hunger. "When you bring protein to about 30% of your daily calories, you'll naturally eat less," says Lauren Slayton, RD, founder of Foodtrainers, a nutrition practice in New York City, and author of The Little Book of Thin. "Protein decreases appetite and also, in my experience, helps you manage cravings."
While studies are mixed about whether consuming more protein leads to weight loss, research is pretty clear that protein can help you retain more of your lean muscle as you lose fat. One 2011 study suggests amping up protein to as much as 1.8 to 2 grams per kilogram (roughly 0.8 to 0.9 grams per pound) of body weight per day to stave off muscle loss when restricting calories. Cut back on refined carbs to balance out the extra calories from adding protein.
You're in middle age
Eating more protein as you get older may help you maintain muscle and ward off osteoporosis, "so you can stay stronger and more functional," says Rodriguez. In a 2015 study, adults over the age of 50 who roughly doubled the RDA (eating 1.5 grams of protein per kilogram, or 0.68 grams per pound, of body weight) were better able to rebuild and retain muscle after only four days, compared with control groups eating the RDA.
Doubling the RDA gives you "optimal protein," a concept that Rodriguez and more than 40 nutrition scientists advanced at a recent Protein Summit, the findings from which were published in 2015 in The American Journal of Clinical Nutrition. Optimal protein works out to be about 15% to 25% of your daily calories, still below the level recommended by many popular high-protein diets. Over a day, that could look like 20-30 grams per meal and 12 to 15 grams per snack, for a total of 90 to 105 grams daily.