Imagine an epidemic that kills more than 300,000 Americans a year. A disease that affects more than 65 percent of the population, and whose incidence among children has tripled in the last three decades. One in which the health-related complications are greater than those of poverty, smoking, and alcoholism, and indirect costs include everything from rising insurance rates and lost work hours to a bump in airfare prices.
It isn't cancer or HIV; it's obesity. And it's a problem that is so multifaceted, with so many contributing factors, that some people have likened it to the crisis in the Middle East in terms of complexity of causes and possible solutions.
"The issue of obesity in our society is one of tremendous complexity," says Dr. Allen Levine. "There is a network of complicated forces interacting, and it's difficult to say any one of them is the root 'cause.' Biology, psychology, society, the government...they all play a role. It isn't as simple as 'nature or nurture.'"
Levine, pictured above, is the dean of the University's College of Food, Agricultural and Natural Resource Sciences (CFANS) and head of the Minnesota Obesity Center. He studies how areas of the brain and certain neuropeptides play a role in obesity and overeating. "I look at obesity and eating from an angle that many people might not think about--eating for pleasure and reward, and how that might overlap with other kinds of 'reward systems' that can become problematic, such as gambling or drug or alcohol abuse."
Humans eat for pleasure, Levine says. Historically, certain foods were considered a "treat" or a true reward. We ate them, and we felt good. The current problem is that we now live in a society that makes those treats commonplace and readily available. Food has become an "acceptable reward," and may result in a type of dependence, according to Levine.
"In a public forum," Levine says, "you're not going to be drinking or injecting yourself with drugs or having sex at work. You can't smoke at your desk. So what are you going to do to reward yourself? Well, you can have a donut. Society isn't going to slap your hand if you eat at your desk. It's a reward, a 'feel good' thing, but it's allowable."
Dr. David Kessler, former commissioner of the FDA and author of The End of Overeating, agrees that eating "bad foods" is indeed as much a matter of our brains as it is our bellies. In his book, he proposes that foods high in fat, salt, and sugar alter the brain's chemistry in ways that compel people to overeat. "Much of the scientific research around overeating has been physiology--what's going on in our body," he says. "The real question is what's going on in our brain."
Foods containing high amounts of sugar, fats, or salt are considered "highly palatable" foods. These types of foods, Kessler says, trigger the brain to release dopamine. Eventually, the brain's dopamine pathways respond even at the suggestion of food--causing intense cravings. When the food is consumed, the brain releases opioids--which bring relief. Together, the dopamine and opioids burn a pathway that activates whenever a person is reminded about a highly palatable food--even if they aren't hungry.
Levine points that, of course, while neurobehavior plays a role, it alone isn't responsible for the dramatic increase in overweight individuals. "It's an intersection of many factors. Clearly, biology is driving people to eat a certain way, their impulse control is not stopping them, and the environment is enabling them. It's akin to intelligence and knowledge in a way...like taking someone who is very, very bright and putting them in a resource-poor environment versus in one in which there are many opportunities for learning. Obviously, they will be more informed and advanced if they're in the environment that educated them well."
In addition, the food industry responds to supply and demand, Levine says. "When the craze was 'fat-free,' suddenly multitudes of non-fat products appeared on shelves. And of course, to make something light, or low-fat, you have to increase the sugar to make it taste good. Plus, it's cheaper for the restaurants to give you more food. Think about it--what does it cost for them to add extra beef to your burger? A buck? But how many more customers will they draw in if their burgers are bigger and juicier than the place down the street?"
And with the rise of convenience foods and the prominence of chains such as McDonald's, comes fatter families because "it's time-consuming and expensive to feed a family healthy foods. High-calorie foods are cheap. Sugar and fat mixed together (cake frosting) is not expensive. But look at the price of fresh fruits and vegetables, at a head of lettuce. On a per-calorie basis, it's a lot more expensive to eat salad than it is to eat cake."
A family with two parents each working 40-plus hours per week, struggling to make ends meet, is much more likely to rely on fast food and prepackaged food, Levine says, because it's "quick, cheap, and easy."
The problem is pervasive and contributing factors can be found in just about every facet of our society--from politics to business and industry, and from education to marketing. Is there a solution in our lifetime? What can we do to avoid the "middle age" spread?
Levine encourages activity and exercise--making moving a habit. Kessler also touts regular exercise, and also believes we need to retrain our brains in order to retrain our appetites. "We did this with cigarettes," he says. "It used to be sexy and glamorous but now people look at it and say, 'That's not my friend, that's not something I want.' We need to make a cognitive shift as a country and change the way we look at food. Instead of viewing that huge plate of nachos and fries as a guilty pleasure, we have to . . . look at it and say, 'That's not going to make me feel good. In fact, that's disgusting.'"
For tips on healthy eating, check out this month's When I'm 64 column.