I teach a college class in exercise physiology at a private university in south Florida. The questions I get are often quite illuminating. Perhaps the topic that engenders more falsehoods is dietary protein. When students realize that only protein and fat are essential (i.e. you need them in your diet because your body can’t make them), whereas carbohydrate is not, the incredulity on their young faces is apparent. And when I mention that protein can actually help them lose weight and bodyfat, a collective nod fills the room. Show me the beef!
A recent study shed light on the amazing effect of supplementing with protein. Scientists compared using a higher-protein supplement vs. a conventional carbohydrate on body composition and physical function in older women during weight loss. Thirty-one overweight or obese women were given a low-calorie diet (1,400 calories—15 percent protein, 65 percent carbs, 30 percent fat) along with either a 25-gram protein supplement or an isocaloric maltodextrin treatment twice a day for six months. Imagine finding out a half year later that, oh, by the way, you’ve been sucking down more sugar than a cotton candy festival.
Results: The protein group lost 8 percent of bodyweight while the carb group lost 4.1 percent. In terms of thigh volume changes, the protein group gained 5.8 percent more muscle and lost 3.8 percent more subcutaneous fat. The researchers concluded that “a higher protein intake during caloric restriction maintains muscle relative to weight lost, which in turn enhances physical function in older women.”
That said, if you want data on which protein to use, whey is the one protein that all of us should eat. It clearly stimulates muscle protein synthesis, defends the body against oxidative stress, plays a role in the immune response and, of course, is instrumental in improving body composition. A recent study found that whey protein supplementation reduced the amount of fat stored in the liver of obese women. In fact, the stuff is medicinal as well as performance-enhancing! A dose of 20 to 40 grams of whey immediately postworkout is what this doctor orders.
Editor’s note: Jose Antonio, Ph.D., is the CEO of the International Society of Sports Nutrition (www.theissn.org); also check out his site www.TheWeekendWorkout.com.
Mojtahedi, M.C., et al (2011). The effects of a higher protein intake during energy restriction on changes in body composition and physical function in older women. J Gerontol A Biol Sci Med Sci. Published online ahead of print. July 27.