by Chris Shugart
Can You Lose 1 Pound of Fat Per Day?
Is it possible to lose a pound of fat per day without losing muscle? Yes, but the plan is absolutely crazy-pants. Take a look.
What's the most effective way to lose fat? Knock roughly 300-500 calories off your maintenance intake, eat about a gram of protein per pound of body weight, and lift weights. It works every time, you probably won't gain the fat back, and it's actually not that terribly difficult.
But forget all that. Let's talk about rapid fat loss – like a pound per day – using an insane diet and a totally bonkers amount of exercise that you can't even do, nor should you even try.
The Study: 4 Days of Dieting, 35 Hours of Exercise
Researchers wanted to see if they could kill some dudes with starvation and extreme exercise. Okay, not exactly, but kinda. Here's what they did:
- Researchers recruited 15 fat guys with 40-inch plus waists, all around age 40.
- The participants consumed only 320 calories per day for four days. Some got their measly 320 calories from whey protein; others got their calories from a sucrose drink (table sugar). This liquid diet was divided into three highly unsatisfying "meals."
- On all four days, the subjects did 45 minutes of a hand-cranking exercise (pedaling with their hands) and then walked on a treadmill for 8 hours. Yes, 8 hours, totaling 22 miles a day.
But Did They Die?
They did not. Here's what did happen:
- Subjects lost an average of 11 pounds of total body weight in four days.
- About 5 pounds of that body weight was fat, so yes, they lost about a pound of fat per day.
- The rest of that lost weight was water. This is typically what happens with any diet plan: the body responds by dumping some water weight (muscle is around 73% water; fat is around 13% water). Your body stabilizes soon after, though.
- Surprisingly, they didn't lose any muscle in the four-day period! Now, if you dig up the full study, you'll think the subjects lost muscle because the researchers said participants lost more "lean mass" than body fat. But that lean mass number includes body water. Luckily, the researchers were as smart as they were sadistic and used both DEXA and bioelectrical impedance to measure water weight.
- Whether they got their 320 calories from whey protein or sugar didn't make a difference between the two groups, probably because it's really hard to lose actual muscle in just four days, even with this nutty plan.
- Fat loss was maintained after the four-day diet/exercise plan for at least a year (when researchers retested everyone). There was no "fat overshoot" – regaining all the fat lost during dieting. Subjects kept most of the fat off, though their body weight increased because of natural water-weight stabilization.
What Can We Learn From This?
Although it takes an extreme, almost-undoable approach, it is possible to lose a pound of pure fat per day, at least in the laboratory. So, um, now we know.
We also learned that overweight/obese people can lose fat and keep muscle in the short term, even with a wacky diet and exercise plan. Although the subjects here were told to eat and exercise however they wanted after the study, they managed not to have any fat rebound.
Keep in mind, already lean folks dieting to get completely shredded are much more likely to lose muscle than overweight dieters. So, don't try this at home. Of course, in real life, this "plan" is unrealistic and certainly not recommended. It was just a study.
Also, remember that a high protein intake when dieting for longer periods unequivocally leads to more muscle retention. Please don't do a table-sugar diet, kids.
Finally, we learned what it actually takes to lose a pound of fat per day. Many diet plans make that claim, but the weight lost is mostly body water. What it really takes is over 9 hours of exercise every day and virtually no food. In other words, it ain't gonna happen out in the real world.
A Saner Approach
Rapid fat loss plans are appealing, and not just because of the rapid part. "Just consume this 106-calorie drink three times a day and walk a lot" is simple and easy to understand. Obviously, this is unhealthy in the long run, which is why the study above only lasted four days.
Instead, shoot for about a pound of fat loss per week, and use a plan that preserves muscle. If you like the simple approach of having liquid-only meals, try The One Day Diet Plan. In short, you'll have one very low-calorie day per week using MD Protein and six maintenance days of regular eating where you toss in 17 minutes of extra walking (which sure beats 8 hours).
Note: Thanks to T Nation contributor Bill Campbell, Ph.D., for highlighting this wacky study in his Body by Science newsletter.
Reference
- Calbert et al. "A time-efficient reduction of fat mass in 4 days with exercise and caloric restriction," Scand J Med Sci Sports, 2015 Apr;25(2):223-33. doi: 10.1111/sms.12194. Epub 2014 Mar 6.