Weight Loss Science, Calorie Deficit Paradox and The Biggest Loser

Weight loss science begins with the calorie deficit.  We’ve shown that cutting calories and creating a caloric deficit during the day, or eating fewer calories than you burn, is the only way to lose weight. However, the paradox is that our metabolism will slow down as soon as we reduce calories.  This makes weight loss harder the more weight we lose.  This paradox is the main reason all the “Biggest Loser” participants gained back their weight.  We’ll explain how this works and how to counteract this phenomenon in your fitness programming. 

Use A Metabolic Analyzer to Measure Weight Loss Changes

Vada is a personal trainer and a PNOE user. She focuses on helping  obese and overweight individuals lose weight. She uses the PNOE metabolic analyzer to understand weight loss science with her clients.  She can verify the extent to which the caloric deficit she prescribes to her clients is creating the weight loss paradox, harming their metabolism and is leading them to a weight loss plateau. 

The Calorie Deficit Paradox 

In previous posts and emails we discussed how cutting calories and creating a caloric deficit during the day, in other words eating fewer calories than you burn during the day, is the only way a person can lose weight. At the same time however, since our body will always try to maintain its current state, cutting calories will stimulate a series of endocrine and hormonal changes that will ultimately cause a person’s metabolic activity to slow down and consequently prevent him from losing weight further.  

A Slower Metabolism Can Be Permanent

It is extremely important to closely monitor a person’s metabolic activity during weight loss since the slow down of a person’s metabolism can be permanent. This will cause the person to always be burning fewer calories than normal. The most famous example is that of the participants of the Biggest Loser, the famous TV show where participants undergo a rigorous weight loss program that leads to a daily calorie deficit of 3,500 kcal! 

 Why “Biggest Loser” Participants Gained Back Their Weight

Although participants were able to lose unbelievable amounts of weight, they ALL regained it a year or so after. And that sparked the interest of several investigators who specialize in obesity. What they found was similar to what other studies have shown. The extreme caloric deficit that participants had undergone had significantly lowered their metabolic rates. In simple words they were burning fewer calories than normal. 

And this didn’t change as they regained weight. In the case of one participant due to the extreme caloric restriction his metabolism slowed so much that he now has to eat 800 calories per day less than a typical man his size just to maintain his current weight of 295 pounds. Anything more turns to fat. His metabolism slowed tremendously as he lost weight during the competition but this didn’t change even as he regained more 100 pounds after the show.

With a slowed metabolism, eating normally means that a person will ultimately regain weight. This is exactly the reason why people who go on diets will ultimately regain the weight they lost unless they figure out a way to either stop the slow down of their metabolism or bring it back to a normal state. 

The Difficulty in Weight Loss is Biology, Not Willpower 

In the words of Dr. Rosenbaum, an obesity researcher at Columbia University:

“The difficulty in keeping weight off reflects biology, not a pathological lack of willpower affecting two-thirds of the U.S.A.,”

Apart from shedding light in the right direction these findings also provide great psychological support to the millions who struggle with weight loss. 

They explain that weight loss is not exclusively a problem of a person’s character but primarily a pathological condition that has a treatment. 

In the words of one of the participants “The shame that was on my shoulders went off,”

Weight Loss Science: How To Counteract Slowing Metabolism

Now let’s see what the treatment is!

First let’s go back to Vada and her client. An overweight female in her 40s that after several years of trying to lose pounds decided to follow a more scientific approach to weight loss. 

These are the results of her first metabolic test. The test was the standard 4 stage protocol built in the PNOE application to work with the PNOE Metabolic Analyzer. What we are looking at in order to understand if an individual is going into a condition of reduced metabolic rate is mechanical efficiency. 

How To Identify the Problem with Metabolic Testing  

Mechanical efficiency is the ratio between mechanical power over metabolic power. Metabolic power or in other words the rate by which our body is burning the energy found in nutrients is nothing more than kcal/min converted in watts!

Mechanical efficiency shows the rate by which our body in converting the energy found nutrients into movement. Or in other words, how many calories we need to burn in order to conduct a specific movement. 

As the metabolic changes occur in our body because of caloric restriction our mechanical efficiency is expected to go up, meaning that our body will burn a smaller amount of calories in order to generate the same amount of movement. 

This in combination with a reduction in resting metabolic rate will ultimately lead the person to burn fewer calories during the day making it harder to lose weight and then having to eat less than normal to keep it off. 

Metabolic Analysis Shows the Reduced Calorie Expenditure 

And this is exactly what started to happen in the case of Vada’s customer. Her metabolic activity slowed and as a result after 3 months of dieting and working out her caloric expenditure at 4 miles per hour went from 9.7 calories per min to 8.8 calories per min. After adjusting for the reduction in weight this corresponds to a roughly 15% reduction in the amount of calories she burns during her activities per unit of body weight. This in combination with a reduction in her resting metabolic rate can lead to roughly 300 fewer calories burnt daily. 

This means that a reduction of 700 kcal per day in food intake has roughly 40% less impact on her ability to lose weight since it now corresponds to just a 400 calorie deficit on a daily basis.

How to Counteract Reduced Calorie Expenditure

This is an indication that Vada should start to take action and reverse this to avoid taking her client into a weight loss plateau. Two methods to reverse the calorie expenditure reduction are weight training or going on a refeeding phase. A refeeding phase is when a person temporarily stops the caloric deficit and goes back to eating as many calories as he or she needs to maintain the current weight. 

Research On The Calorie Deficit Paradox

A recent review study showed that:

“Maintenance of a 10% or greater reduction in body weight in lean or obese individuals is accompanied by an approximate 20%-25% decline in 24-hour energy expenditure. This decrease in weight maintenance calories is 10–15% below what is predicted solely on the basis of alterations in fat and lean mass. Thus, a formerly obese individual will require ~300–400 fewer calories per day to maintain the same body weight and physical activity level as a never-obese individual of the same body weight and composition” 


Learn About the PNOĒ PrecisionDiet™ Service

It’s a new service for health and fitness professionals based on clinically accurate metabolic testing with the PNOĒ Metabolic Analyzer.  Help your clients succeed in all their health and weight loss goals with revolutionary precision and coaching support for monthly nutrition, diet, workouts and tracking.  Get more details at http://www.mypnoe.com/precision-diet-weight-loss-program


Interested in using the PNOE Metabolic Analzyer for your own business or personal use, to measure and analyze metabolism and to help calibrate smartwatches and wearables?  Get in touch with us below.