WebMD Medical News Laura J. Martin, MD July 15, 2011 -- All
protein may not be created equal when it comes to weight loss.
Whey, or milk, protein may offer people who want to slim down a
slight edge over soy, a new study shows. Researchers at the U.S.
Department of Agriculture's Human Nutrition Research Center
randomly assigned 90 overweight and obese middle-aged adults to
one of three groups. The first group was asked to add protein
drinks made with whey to their normal diets, the second group
drank protein drinks made with soy protein, and the third group
drank carbohydrate drinks. Study participants weren't told which
group they had been assigned to. All the drinks, which were
drunk twice daily, at breakfast and dinner, had the same number
of calories: 200. They also all had had 52 grams per packet, for
a daily total of 104 grams of added protein or carbs.
Researchers tracked participants' physical activity levels,
weights, waist sizes, lean and fat body mass, and blood levels
of hormones related to hunger