Hello and

today's show was your host, Monica Reinagle,

and today's show was suggested by Fabio, who writes,

I came across a study on bodybuilders which suggests

that a caloric surfeit doesn't contribute to weight gain as you would expect when the extra

calories come solely from protein. Can you comment on it?

The study Fabio asked me about was published in 2014 in the Journal of the International

Society of Sports Nutrition, and it is definitely worth a closer look.

The subjects in this study were all in their early 20s and they were all engaged in heavy

resistance training or weightlifting.

They were quite lean and very muscular going into the study.

In fact, if you had looked only at their body mass index,

their BMI numbers, it looked as if the subjects were on the verge of obesity, but when you

look at their body composition, it's clear that the higher body weights relative to their heights

were due to their very high muscle mass.

One group in the study then added a lot of extra protein to their diet

in the form of whey protein powder.

And when I say a lot I mean a lot these athletes had previously

been consuming about one gram of protein per pound per day or about 20 to 25 percent of their calories.

Now, this is about twice the recommended minimum intake,

but it's still comfortably within the acceptable range

for protein that's laid out by the National Academy of Medicine,

...