THE OBESITY LIE: "A CALORIE IS JUST A CALORIE"
Almost Half of Americans are now Obese
ROBERT LUFKIN
2024

We are now in the worst global epidemic of obesity that the world has ever known. Being “overweight” means having more body weight than is considered normal or healthy for one’s age or build. “Obesity” is an even more severe state of having an excess amount of body fat—and it’s not just affecting older people. Statistics show 42.5 percent of adults ages twenty and over are obese, and 73.6 percent are at least overweight.
Almost half of Americans are now obese, and most are overweight! Obesity is unhealthy and a marker for metabolic dysfunction, which manifests as hypertension, diabetes, heart attack, stroke, Alzheimer’s, cancer, and other chronic diseases.
Our understanding of the causes of this epidemic and the approaches to treating it is based on a simple lie: that “a calorie is a calorie,” implying that obesity is caused by eating too many calories.
This is wrong for two reasons. First, calories in themselves are not sufficient to create obesity. Some other cause is needed. Also, different types of calories have different effects on this controller of obesity.
To say that obesity is caused by eating too many calories is like saying that alcoholism is caused by drinking too much alcohol or that a heart attack is caused by the heart muscle not receiving enough oxygen. These are all true, strictly speaking, but they give us little insight into any ultimate cause that can meaningfully affect the outcome.
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A calorie is defined as a measure of the energy that food provides. We all need energy and calories to live. The lie is that it doesn’t matter which foods provide them because all calories are created equally. Therefore, if you want to lose weight, just eat fewer calories.
This lie came from the idea that all our energy comes from the calories of the food that we consume, which is correct. The first law of thermodynamics—that energy and calories are conserved—is also used as a line of support for the lie. For example, a recent paper argued: “Thermodynamics dictate that a calorie is a calorie regardless of the macronutrient composition of the diet.”
This is also referred to as the “energy balance theory of obesity.”
But the equation calories eaten = calories burned is an oversimplification. Because, as any person who has struggled with extra pounds knows, calories eaten can also go to fat (and glycogen) storage instead of being directly burned. So, the equation really should look like this: calories eaten = calories burned + calories stored.
The key control point for weight gain is how many of the calories we consume are sent to be stored versus those burned. That number doesn’t depend on the total number of calories but instead on a biochemical signal in our bodies.
That signal is produced by a hormone called insulin. Insulin tells the cells to store calories primarily as fat. If no calories are stored as fat, then they will be burned. There will be no weight gain. If insulin is turned on and fat storage occurs, fewer calories will be burned. Insulin status directs calories toward either fat storage or burning for energy.

Insulin Status
And how they affect calories
Also, if the insulin is not activated, a person will not store calories as fat, no matter how many they consume. They won’t gain weight but will burn all the calories.
One example is this child (pictured below) who is unable to produce sufficient insulin in his pancreas because of type 1 diabetes. No matter how many calories he ingested, he was unable to gain weight (left image). After eight weeks of added insulin treatment, he had gained weight (right image). Unless type 1 diabetics receive supplemental insulin treatments, they have little body fat, no matter how many calories they consume.
As a physician, I also know from personal experience that I can make anyone gain weight or fat just by giving them extra insulin. This is seen in both type 1 and type 2 diabetics as soon as they begin taking extra insulin as a medication.
To put it another way, calories are necessary but not sufficient to drive obesity. Insulin is required. Obesity is not just a calorie problem; it’s an insulin problem. If all foods stimulate insulin equally, then a calorie is just a calorie. That’s not a lie. But all foods don’t trigger insulin the same way.
Of the three dietary macronutrient categories that we will cover in detail later, carbohydrates strongly stimulate insulin, proteins mildly do, and fats hardly stimulate insulin at all.
So, a calorie from carbohydrates will drive more insulin (and weight gain) than a calorie from protein, which will drive more insulin than any fat calories. All calories do not have the same effect on weight gain. Therefore, weight loss is not just about fewer calories.
The truth here is that in order to lose (or gain) weight, the most important thing is not the number of calories consumed but rather the types of calorie that affect the insulin levels and direct our bodies to store energy as fat.
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As every rancher knows, to fatten livestock, simply feed them large amounts of refined carbohydrates that will turn on insulin and drive energy storage into fat. Feeding livestock fatty foods will not have the same effect.
What is the reason for our growing numbers of obesity? The conventional wisdom and medical advice are that to lose weight and prevent obesity, we need to exercise more and eat less. This assumes that it doesn’t matter what you eat, just how many calories. Obesity is viewed as some sort of defect in willpower in an individual by not being able to control their impulses.
This is based on the acceptance of the “energy balance model of obesity,” which is taught in medical schools around the world. But as the “success” of Jenny Craig, WeightWatchers, Nutrisystem, and innumerable other weight-loss companies demonstrate, it doesn’t work. Just look at their recurring customers.
How did we get to this situation? During the 1970s, when attention became focused on heart disease and there was a slight increase in obesity, American politicians held hearings about how to best advise the public about their diet as a national health policy.
In 1977, a group of scientists issued the first set of Dietary Guidelines for Americans, which the US Department of Health and Human Services (HHS) and the US Department of Agriculture (USDA) update roughly every five years. They urged Americans to increase their carbohydrate intake to 55 percent to 60 percent of their total daily calories and to reduce fat intake to 30 percent to 35 percent. This was done primarily to reduce what they considered the risk of heart disease (also a lie—more on that later).
This guidance meant people should eat more sugars and carbohydrates and cut back on saturated fat from meats, eggs, butter, and whole milk. Rather than consume what they called “bad” saturated fats, we were told to eat low-fat foods (such as skim milk) and replace saturated fats in animal products with polyunsaturated fats from inflammatory vegetable oils (such as soybean oil) and trans fats.
In 1992, these first flawed guidelines were replaced by even worse recommendations—the food guide pyramid.
At the base of the pyramid were carbohydrates, especially refined ones such as breads, pasta, rice, and cereals, of which we were told to eat six to eleven servings a day!

Food pyramid
Learn to eat healthy
By replacing the consumption of fats (which have little effect on insulin) with carbohydrates (which strongly stimulate insulin release), the metabolism for most Americans who followed this advice changed from burning calories to storing them as fat.
The number of calories from fat was reduced, and the number of calories from carbohydrates increased. By replacing the fat calories with carbohydrate calories, we turned up insulin and sent the message to store fat.
And store fat we did. At about the same time that we substituted carbohydrates for fat in our diets, the obesity rate skyrocketed—and it hasn’t slowed down since.
The medical system doesn’t fully agree on the actual reasons why obesity is happening or how to stop it. Yet the problem is getting worse—and people are dying.
In Lies I Taught in Medical School, Dr. Robert Lufkin critically examines misconceptions in conventional medicine, particularly around nutrition, metabolism, and chronic diseases. Through personal experience and research, he explores how widely accepted medical advice may be contributing to poor health outcomes and offers a fresh perspective on understanding and managing these conditions.