by Chris Shugart
Lose Fat Without Really Trying
Burn extra calories and oxidize more fat all day and all night, even when eating at maintenance intake. Here's how.
If I were given a million-dollar advance to write a diet book, I could sum it up in one sentence:
Eat about a gram of protein per pound of body weight.
This single action autoregulates and trends the body in the right direction: less fat and more muscle. Then, to cash that fat check, I'd add a whole bunch of science, some recipes, and quite a bit of repetitive filler to satisfy the publisher's page quota. Aren't you glad I summed it up for you in one sentence?
The big question is, "Why does that work?" You might think it has something to do with satiety or protein's greater thermic effect. You wouldn't be wrong, but there's more to the protein story. A fascinating study gives us another chapter.
The Study: Locked in a Room for 32 Hours
Researchers recruited 43 healthy men and women and locked them in a weird room for 32 hours… twice.
The room is called a whole-body calorimetry unit. This chamber is like a big machine that measures energy expenditure. This, along with some other sci-fi gadgets and tests, allowed the researchers to see the difference between calorie intake and expenditure (energy balance). They also looked at fat balance: dietary fat consumed, and dietary fat burned for energy.
The participants of the study were divided into two groups:
Group 1: Normal Protein Control Diet – This group got three meals and two snacks on the first day, slept in the weird calorie room, and had breakfast on the second day. All of these were pretty standard whole-food meals. They consumed about 2100 calories, with 83 grams coming from protein.
Group 2: High Protein Diet – This group also consumed 2100 calories divided over several meals, but their diets contained 211 grams of protein. That sounds good, but their "meals" consisted of soy protein powder and olive oil blended into low-fat milk. Gross!
Now, 2100 calories was the participants' maintenance intakes, which shouldn't cause weight gain or loss. Both groups walked on a treadmill for 40 minutes and then just sat around. A few weeks later, they switched groups and did it again (a crossover design study). And remember, they consumed the same number of daily calories in both groups. Only protein intake differed.
What Happened?
- The high-protein diet triggered a larger energy expenditure compared to the normal-protein diet.
- The high-protein eaters burned around 80 calories per day more compared to the average-protein eaters – 4% more calories.
- The high-protein eaters even burned 17 more calories while sleeping than the normal-protein eaters.
- On the second day of the diet, both groups had breakfast, either a modest-protein whole-food meal or a high-protein shake. The researchers measured energy expenditure during their remaining six hours in the whole-body calorimetry unit. The normal-protein eaters burned 75 calories. The high-protein eaters burned 100 calories.
- Regarding the fat balance data, the high-protein diet lead to a negative fat balance (they oxidized more dietary fat). The normal-protein diet lead to a neutral fat balance.
- Based on the 24-hour respiratory exchange ratio, the high-protein eaters burned more body fat all day long.
- When the researchers ran the energy balance math, the high-protein group showed a slightly negative energy balance (-18 calories). The normal-protein group showed a moderately positive energy balance (+92 calories). So that's a 110-calorie difference between the two groups.
Bill Campbell, Ph.D., makes this important note: "What's essentially happening here is that you're getting a calorie-deficit-like effect without actually reducing your calories. It's occurring by manipulating daily protein intake."
How to Use This Info
Eat a high-protein diet if you're not already doing it. Remember, the study participants above were normal-weight folks who bumped their protein up to 211 grams a day.
Greater energy expenditure, more calories burned, more fat oxidized, and achieving a mild calorie deficit without actually being in a calorie deficit? Yeah, sign me up. And imagine the long-term body composition effects. This study took place over 32 hours. Extend that into weeks or months and your body will look (and feel) dramatically better.
Also, I'd love to see this study repeated with a better-quality protein source for the high-protein group. I mean, it's like they chose the least-good protein (soy) they possibly could. They must've been on a tight budget because soy is generic dog food protein.
While it might not make a big difference in just 32 hours, over time, a whey-casein blend is a superior choice for metabolism, muscle building, and more. And it doesn't taste like dirt. MD Protein (Buy at Amazon) is the protein connoisseur's choice.
That aside, this study once again proves that protein is a powerful fat-loss agent and not just for building pretty muscles.
Note: Thanks to Dr. Bill Campbell for breaking down this study in his Body by Science newsletter.
Reference
- Oliveira, et al. "A high-protein total diet replacement increases energy expenditure and leads to negative fat balance in healthy, normal-weight adults," Am J Clin Nutr, 2021 Feb 2.