Have you noticed? Although not a straight-up Atkins revival, protein is one of the hottest diet and nutrition trends today. From the newly popular “Paleo” diet (i.e. meat, vegetables, and other whole foods a caveman would have recognized) to the demonization of wheat and other grains—fed by growing ranks of gluten abstainers as well as diet titles like Bread is the Devil (St. Martins, 2011)—Americans are again turning to protein for nutritional and weight-loss salvation.

New research lends credence to the faith. Eating a low-carbohydrate diet (with unlimited protein and healthy fats) just two days a week reduced weight, body fat and insulin resistance more effectively than eating a calorie-restricted Mediterranean diet seven days a week, in a recently published, four-month study from the Genesis Prevention Center at University Hospital in South Manchester, England. Subjects who ate a 10 percent protein diet ate 12 percent more calories on average than those who ate a 15 percent protein diet, in another recent study at the University of Sydney.

Other studies have linked eating red meat (especially processed meats) with increased mortality risk and other health woes, so what kind of protein remains a good question. Lean meats in moderation, fish, beans and other vegetable proteins, eggs and Greek yogurt all get mostly good reviews. Whey protein is another winner, with studies backing benefits from greater loss of body fat to support for detoxification and anti-inflammatory effects.

To read more on how eating fewer carbs and more protein, more often (along with short, intense cardio workouts) can help balance hormones and “reset” metabolism, read "The hormone balance plan."