Are we eating too much protein? Not enough? Nutritionist Carrie Dennett wants to clear some things up.

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On Nutrition

In the space created by the confusion about whether to demonize dietary fat or carbohydrates, protein seems to have emerged as the “safe” macronutrient. If you doubt its popularity, just look at the plethora of protein shakes, jerky snacks and energy bars. We certainly are getting the message to eat more protein.

But there’s also the opposing message: Americans eat too much protein. A few weeks ago, I read these words in another major newspaper: “The recommended intake for a healthy adult is 46 grams of protein a day for women and 56 grams for men.” I sighed heavily and started writing this column.

As anyone qualified to provide nutritional advice to humans knows, the recommended intake of protein is not the same number for everyone; it’s dependent on an individual’s body weight. Precisely, the recommended daily intake of protein is 0.8 grams per kilogram of body weight (to find your weight in kilograms, divide your weight in pounds by 2.2). That means that 46 grams of protein is adequate for a woman who weighs 126.5 pounds, while 56 grams is adequate for a man who weighs 154 pounds. Does that match what you weigh?

You’ll notice that I said “adequate,” not optimal. Increasingly, research is showing that the recommended daily intake is adequate for replacing protein we lose through bodily waste, etc. That doesn’t make it optimal for building and repairing muscle. We lose about 1 percent of our muscle each year after about age 30 unless we actively take steps to counter that loss. That means adults may need 1-1.2 grams of protein per kilogram of body weight each day. For example, someone who weighs 150 pounds needs 68 to 81 grams of protein per day. For an easier estimate, just divide your weight in pounds in half.

One of the biggest myths circulating about protein is that we already get enough. If you’re sitting across from me in my office, I don’t care how much protein the “average” American is eating. I care how much you’re eating. You might be eating too little protein, you might be eating too much, or you might be right on target.

I also care about what time you’re eating your protein-rich foods. There’s more to getting “enough” protein than just eating a certain amount in the course of a day. This is one instance where timing does matter, because your body is constantly making and breaking down muscle. Research suggests that to maximize your body’s muscle repair and building machinery, you need to distribute protein fairly evenly across your day, especially once you are no longer a “young” adult.

Contrary to another popular myth, protein is not “hard” on normal kidneys — the National Kidney Foundation even says so. What may not be ideal for health, according to a substantial body of research, is excess animal protein. Fortunately, you can get protein from many plant foods, and there are good reasons to do so. A recent Harvard study found eating a diet rich in healthful plant foods and fewer animal foods is linked to reduced risk of heart disease. A similar study found the same thing for risk of type 2 diabetes. Protein-rich plant foods contain extra health-boosting features like fiber, healthy fats and a host of vitamins, minerals and phytonutrients. Overall, beans, lentils, nuts, seeds and soy foods are the most protein-rich plant foods, while grains and vegetables contain smaller amounts.