Copyright © 2009
by Daniel Matthew Korn

All Rights Reserved

It is popularly assumed that people who are overweight have eaten too much or have eaten “bad” or “fattening” foods. Many psychological reasons are given for why people do this, such as boredom, laziness, and the abundance of food. However, while people who are overweight have eaten too much, there is evidence that their reasons for doing so are physiological rather than psychological.

Although it is counterintuitive, or contrary to the way we naturally think, people who have gained weight by eating too much are likely to be hungrier than those who have not. Since eating usually causes us to feel full, and not eating causes us to be hungry, why overweight people are hungrier than thin people has been a mystery. It has been called the hunger-obesity paradox by health researchers.¹

One of the popular explanations for this paradox among researchers is that it is caused by food insecurity. The theory goes that it is poor people who are most likely to be overweight, and people who are poor are more likely to be fearful about their future ability to feed themselves. This stress then causes food-insecure people to overeat.

There are many problems with this explanation for the hunger-obesity paradox. While poor people in the United States are more likely to be overweight,² in China it is rich people who are more likely to be overweight.³ This seems to rule out food-insecurity as a cause of the hunger-obesity paradox.

Thus, we are left with a very important paradox, without a conventional explanation. However, this paradox points to the mechanism responsible for the obesity epidemic. As a society, we are gaining weight because we are hungrier. When we look for the cause of weight gain and for what might produce weight loss, we need to look for things that will have an effect on our hunger.

This is a major departure from traditional dieting and medical advice. Indeed, you cannot buy packaged food at a supermarket in the United States without the amount of calories being displayed on the packaging. At the same time, we have almost no awareness of what will make us hungrier, and we have collectively become much hungrier.

In the U.S., both the amount of food produced per person and the amount of food eaten per person have dramatically increased in recent history. In 1978, we were producing 3,200 calories of food per person. By 1999, the food industry was producing 3,900 calories of food per person.⁴ Adjusting for a higher amount of waste, over two decades we increased food consumption by 418 calories per person.

This explains the average increase of Americans’ weight over the same period. It is not that we are eating more simply because more food is available. After all, food is subject to the same economic laws of supply and demand as any other product. If farmers produced more food than was being demanded, they would create a surplus. A surplus would cause prices to drop and lower the incentive to produce food. This would cause production to fall until a new equilibrium was reached.

This extra food is being demanded and consumed. What we see in these facts is the effect of the hunger-obesity paradox on the national level. Americans are eating more because they are hungrier, and they are hungrier despite eating enough to gain substantial amounts of weight.

What is needed to solve the problem of weight gain is not a way to will ourselves to eat less. We must identify the cause or causes of the increased hunger we are experiencing in the modern age. Some of these causes are, in fact, known and studied, but they are usually ignored in popular books on diet. In the next chapter, we will look at prescription drugs that are known to cause weight gain. In most cases, these medications cause weight gain by increasing hunger.

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Citations:

²Idem.

³Briefing | Asia: China: Affluence Brings Obesity." New York Times. 4/04/2009 http://query.nytimes.com/gst/fullpage.html?res=9905EFD7113FF934A35752C1A9609C8B63.

⁴David M. Cutler, Edward L. Glaeser, and Jesse M. Shapiro. "Why Have Americans Become More Obese?" Economic Research Service. 4/04/2009 http://www.ers.usda.gov/publications/efan04004/efan04004b.pdf.