I’m fond of this macronutrient powerhouse for so many reasons: It promotes healthy skin, hair, nails, bones, and muscle. It’s also a fabulous weight-loss aid, according to a 2005 study from Arizona State University. Protein increased satiety (satisfaction and feelings of fullness) and increased after-meal calorie burn. In other words, eating protein-rich meals, rather than higher-carbohydrate ones, leads to more satisfaction, less hunger, and more fat burn. I love that: three benefits in one. Earlier research also found that people following higher-protein diets generally decrease their food in take by an average of 10 percent (about 200 calories).