The Most Powerful Nutrient for Fat Loss

[T_Nation]

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 you want to lose body fat, eat a high-protein diet. Study after study – and real-life human after real-life human – proves it.

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 every damn time with every damn body?” 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 gathered up 43 healthy men and women between 18 and 35 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: basically, dietary fat in (consumed) and dietary fat out (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.

Yada, Yada, Yada… 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. Metabolic Drive (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 most-excellent Body by Science newsletter.

Reference

Reference

1. 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.

[Healthyguy]

Great article! What would have been cool is having a third group of high protein people, but better protein choices to see if that made a difference as well.

[toughguy]

@Healthyguy

have been cool is having a third group of high p

Agreed! Excellent article.
Testing three times, or conducting experiments with repetitions, is a common practice in science.

[Chris_Shugart]

Agreed. But I give the researchers some props for successfully finding 43 people of various ages (not just college kids) to stay confined in a whole-body calorimetry unit for 64 total hours. Sometimes these look like small hotel rooms and sometimes jail cells!

[NickDube]

What I thought was pretty fascinating and encouraging (at a glance at least) was that they grabbed what is widely acknowledged as a lower quality protein source imperfectly accompanied by other nutrients…and the idea that this consumed in greater abundance than the higher quality protein really seems to emphasize a realistic route for most people in increasing performance and aesthetics. Pretty amazing to consider potential effects had there been a third high protein test group given all high quality from meet and dairy.

[AlexVS]

There seem to be limited practical application of this research.
First, the “normal” protein intake is quite low for the target audience of this site. Most people who are here would already eat closer to the high protein group.
Second, 110 cal a day difference is quite small. Calorie-wise it’s equivalent to an average size apple. So caloric intake is still very important. And for many it would be easier to eat an apple less per day than to stuff 211 gram of protein - unless they already do so.

[Chris_Shugart]

Or eat more protein and stay full to simulate a mild caloric deficit without having to obsessively count calories or micromanage apple intake. I choose that one.

[AlexVS]

I disagree. 110 cal per day (or even less for your target audience) is a difference just too small to be able to just increase your protein intake and stop counting calories.
The only research I’m aware of on this subject found that people easily underestimate their caloric intake by as much as 1,200 cal per day. 110 cal cushion is simply not sufficient.
I wish you were right though.

[TrainForPain]

At the end of the day, as you note, we have to create a deficit to lose weight. Certainly, caloric control is required. Why not stack your odds by also increasing your caloric burn?

If this was a finance class, an extra $100 doesn’t mean I no longer have to save my money to pay my mortgage… I’m still not going to turn it down.

[Chris_Shugart]

Do you have to count calories all the time? Totally understandable for an obese person who has no clue about calories and needs to learn. It’s a great temporary tool - a tool than can be discarded after a while.

Also understandable for someone in contest prep, which is basically adopting a short-term eating disorder to reach a goal.

But here’s a hot take: if you can’t control yourself and have to count calories daily to avoid getting fat, that’s a full-blown eating disorder. You’re not controlling food; food is controlling you. And study after study shows that a high protein intake takes care of calorie control (autoregulation) and has metabolic effects that trend the body in the right direction.

And yes, obese people overestimate daily cals by 1000+. But what else are they doing? Eating a low-protein, junk food diet. Put two protein shakes in them a day and they’d start losing weight, whether they counted calories or not.

Reminds me of my old “chicken breast challenge.” You can eat all you want. Now, try to get fat on that. Try real hard. Darn near impossible.

This is part of the Protein Leverage Hypothesis.