Is Exercising More or Reducing Calories the Answer to Successful Weight Management? What You Need to Know About the Science of Weight Loss

Which of these statements have you heard?

“To lose weight, all you need to do is eat less and exercise more!”

“Losing weight is all about calories in and calories out.”

“All calories are the same—a calorie is a calorie is a calorie.”

 

For years this is what we were taught in nutrition and exercise physiology classes, and it’s what we told our patients.

Recent research is showing that these statements don’t paint the whole, complex weight loss picture. But before we dig deeper into what we’re learning now, let’s get an overview of the ugly reality of weight and fatness in the United States.

 

The discouraging facts—

  • In 1990, 15% of adults were classified as obese.
  • Now, at least 71% of Americans are considered to be overweight; nearly 40% are clinically obese.
  • Sadder still is that 17% of kids and teens are obese. When I was a kid it was rare to have a fat kid in your class. (I know that blunt statement sounds mean, but we need to start calling it like it is: these kids are in serious danger of having premature health problems and living burdened lives saddled with chronic health issues.)
  • Excess body fat dramatically increases the risk of serious health problems, like:
  1. Type II Diabetes
  2. Heart Disease
  3. Depression
  4. Respiratory problems
  5. Major cancers
  6. Fertility problems
  • Millions and millions and millions of us spend billions on diet pills, special meal plans and group weight loss programs, and gym memberships.
  • The National Institute of Health considers the problem to be so dire that the organization provided 931 million dollars in 2018 to research the problem.

 

What does the recent research show?

So what has all of that money and research shown us? The answer is both complex, and a relief.

Scientists have concluded that a calorie is not always a calorie, and that it’s not as easy as calories in and calories out.

What they have found is: it’s the composition of the food you eat rather than how much of it you can burn off exercising that allows you to sustain, and maintain, weight loss.

And these scientists know something else: the diet that’s best for your friend is probably NOT the best one for you!

Evidently people’s individual responses to diets vary enormously. But what they’re not absolutely sure about is why that’s true.

 

So what’s a dieter to do?

Apply yourself to finding out what works for you! And that may require some trial-and-error time.

 

A story of the dreaded calorie and counting it—

Before WWI, scientists throughout Europe had been focusing on and studying the concept of a calorie being a unit of energy. In college, that concept was hammered into my head, and into my nutrition calculations. We studied bomb calorimeters— wonderful devices you put food into and burned so you could determine just how much energy was released during the destruction process. That gave you the calorie count for that particular food item.

But in WWI, in the midst of a global food shortage, the United States wanted a way to prompt people to reduce their food intake. So the government devised its first-ever “scientific diet” for Americans to follow. At its core was the concept and practice of counting calories.

The following decades saw bone-thin bodies as the ideal body structure, so dieting plans were developed along the idea of eating low-calorie meals. One example of this is the still–popular grapefruit diet, where you consume half a grapefruit at every meal. People believed the grapefruit enzymes were natural fat burners. Then the cabbage-soup-every-day diet appeared. I’m not sure what they thought the cabbage might contribute, except to enhance digestion and whisk the fat away.

Then in the 1960s, a woman named Jean Nidetch and her co-founders became insta-millionaires with their Weight Watchers meetings program. She turned a small, weekly encouragement meeting she held in her living room into a billion dollar (today) business.

Her idea promoted that if you ate less fattening food, then the weight would disappear. That helped propel the late 70s idea that if you just eat less fat, you’ll be less fat. I remember promoting that erroneous idea in the 80s. Based on what I’d learned in school, it seemed to make sense—fat gets stored in the body as fat, so if you consume less of it, then you should wear less of it.

How did that work out?

Not well. Not only did people not lose weight, they actually gained weight!

 

The metabolism factor—

Something else scientists have found contributes to what’s been a frustrating mystery.

When you lose weight, your resting metabolism (the energy your body burns while at rest, just to keep the system going) actually slows down. And when you gain back some of the weight, that metabolism doesn’t speed up. It remains stubbornly entrenched in slow mode. And the number of calories a day it doesn’t burn can be startlingly high.

For some contestants on the reality show The Biggest Loser, their metabolisms registered at burning around 700 fewer calories per day than they did prior to their fat burning journey on the show!

But my question is: could that result be due to the fact that contestants lost a huge amount of weight in a very short period of time, something doctors do not encourage, for a variety of reasons, including heart health.

 

Regardless of the answer, the sad truth is that most people replenish their lost weight at two to four pounds per year.

On the surface, this finding seems to support the idea that the body undermines your efforts to take away what it wants to keep.

 

More of the weight loss story—

Some people—and you probably know one—seem to succeed in losing weight with any diet approach.

Yet there is a bright side to the story.

Take a group of people eating a low-carb diet and compare them to a group following a low-fat plan, and you see almost no overall difference in the weight loss results.

What you do see, however, are three types of people: those who lose a lot of weight on the plan they’re following; those that stay stagnant, with no weight loss; and those that actually gain weight.

Do scientists understand why that happens? Unfortunately, not yet, but they are making inroads to cracking the secret.

 

Rena Wong, a Brown University professor of psychiatry and human behavior has been tracking dieters for 23 years through the National Weight Loss Control Registry (NWCR). What she and her colleagues have found is that most of the people on the list have lost significant amounts of weight—a minimum of 30 pounds—and been able to keep it off for several years by varying means.

The significant finding? Most of these people had to try more than one diet before landing one that worked for them.

 

How did these dieters keep their lost weight off?

It turns out that the most successful dieters have some similar characteristics:

  • Most modified their diet in some way.
  • Most reduced how much food they ate in a day.
  • 94% increased their physical activity.
  • The most popular exercise among them was walking.
  • Most ate breakfast on a daily basis.
  • Most weigh themselves weekly, in order to keep an eye on weight creep.
  • Most watch less than 10 hours of television weekly.
  • Most exercise a minimum of an hour every day.

 

And they also have similar attitudes and behaviors:

  • Most do not consider themselves to be hard-charging, super-performer Type A’s.
  • Most are self-described morning people.
  • Most were motivated by a health scare; a desire to live a longer, healthier life; and to be able to spend more time with their loved ones.
  • And they were highly motivated to find what worked for them and to persevere.

 

Take-home lessons for us:

This information can be disheartening and encouraging.

It tells us that we can lose weight, if we diligently try to find the method that works for us, stay determined and positive, and persevere in best diet practices for our body, at any age.

It’s nice to know that there’s more to the story. It gives many of us a sense of relief and re-invigoration of determination and hope.

And I think it’s important for us to always remember that a loving God fearfully and wonderfully makes all of us. He starts knitting us together in our mother’s womb.

 

I know only too well how easy it is to throw up your hands in frustration when the one-size-fits-all plan fails you. But I invite you to rejoice over your uniqueness, knowing that you will find something that gives you success, if you want it badly enough and are willing to stick with it.


NEXT WEEK: How to find what diet and exercise regimen works for you.

Until then, take heart, you can find success if you know the science of weight loss!

Blessings,

Andrea

“Certainly there was an Eden….We all long for it, and we are constantly glimpsing it.” —J.R.R. Tolkien

For more information on this particular research, see the article “Why Tour Diet Isn’t Working and What to Do About It by Alexandra Sifferlin in Time magazine’s special edition publication The Science of Weight Loss, 2019.