Protein is one of the building blocks of a healthy diet, but most of us are taking in way more than recommended. Women in their twenties and thirties are now ingesting an average of more than 75 grams a day--nearly two-thirds higher than the U.S. Department of Agriculture's recommendation of 46 grams.
While protein-packed energy bars, desserts, and even the popularity of the paleo diet may be partially to blame, many of us are also timing our protein intake all wrong--leading us to consume way more of this macronutrient than we need. "We're not pythons," says Douglas Paddon-Jones, Ph. D., a professor of nutrition and metabolism at the University of Texas Medical Branch in Galveston. "We can't eat an entire chicken and use its protein for the rest of the week." In general, your body can process only 20 to 30 grams every two to three hours or so, max; anything more than that might be stored as fat.
Paddon-Jones and colleagues conducted a study to prove this, comparing the muscle-boosting benefits of two beef meals--one containing 30 grams of protein (roughly the amount in three ounces of chicken) and one with triple that amount. They found that people who ate the larger meal didn't get any additional benefits (just extra calories); blood samples and muscle biopsies showed no increase in muscle protein synthesis (i.e. growth).
Unfortunately, the average steak is 144 percent bigger than the USDA recommends. "Dinner tends to be a protein festival, " says Paddon-Jones. Meanwhile, we skimp on it at breakfast, loading up instead on fast-digestion carbs like bagels or cereal.
Ideally, you want to spread protein evenly throughout your day, aiming for 20 to 30 grams at each meal and between 5 and 10 grams in every snack.
Even within these loose parameters, there's wiggle room in your personal protein numbers depending on your age, build, and activity level. Weight lifters obviously need more than couch potatoes, but a taller woman will also need more than a petite one. So rather than aiming for a set number of grams each day (because; so you really need one more thing to keep track of?), try following the recommendations, which are based on your lifestyle and needs.
* You work out for about a half hour daily: You need at least 61 grams.
* You're training for a big race: You will need 73-123 grams.
* You're pregnant or nursing: You need at least 68 grams.