Want to lose more weight — use whey protein or milk protein — not soy. That's what a new study says — and article I found at WebMD suggests whey, or milk, protein may offer people who want to slim down a slight edge over soy. And, frankly, most milk proteins taste better than soy. That's just my opinion, and I am a soy-milk user.
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 and metabolism.
They also had people keep records of the other foods they were eating. The researchers made sure participants were drinking the shakes during random urine tests for levels of a chemical tracer they had added to the powders.
Seventy-three people completed the study, which is published in the Journal of Nutrition.