American waistlines continue to expand at alarming rates, and efforts to convince people to eat better and exercise more are failing, said Yale University's Kelly Brownell, PhD.
In fact, the obesity crisis is slowly spreading around the globe, said Brownell. According to the American Diabetes Association, diabetes rates are expected to increase by 76 percent in China and by 134 percent in India by 2030.
"Not a single country in the world fails to show increasing prevalence of obesity," said Brownell.
Part of the problem is that psychologists and other researchers remain focused on obesity treatment rather than prevention, Brownell said in a plenary talk at APA's Annual Convention. Meanwhile, people fight an uphill battle against the "toxic food environment," one that's overflowing with fatty foods and sugary beverages. The cherry on top: All of these products are aggressively marketed -- especially to children.
Given this reality, psychologists should step up research on food and addiction and harmful marketing to give policy-makers the science they need to curb the food industry's most dangerous practices, Brownell said.
"We need to take a different approach," said Brownell. "Business as usual is unacceptable."
Feel a sugar craving coming on? Emerging research indicates that food and drugs activate the same reward circuitry in the brain, Brownell said. Princeton University neuroscientist Bart Hoebel, PhD, for example, has found in animal studies that sugar acts on the brain in ways similar to that of highly addictive drugs such as morphine.
"More needs to be done, but this is pretty interesting and it does line up with what some of our patients tell us about how food affects them," Brownell said.
Beverage consumption is also emerging as a hot research topic, Brownell said. In the last four decades, the portion of calories people consume in beverage form has dramatically increased, and the number of available sports drinks, energy drinks, mixed fruit juices and soft drinks swells each year. But food researchers suspect the human body hasn't evolved to handle so many liquid calories, said Brownell.
Plus, many of these drinks pack a double whammy, loaded not only with sugar, but with caffeine.
"Caffeine is bringing people back to the sugary substance time and time again," said Brownell.
Artificial sweeteners found in flavored waters and diet sodas complete the dicey picture, Brownell added. While many consumers believe low-calorie sweeteners are controlling our weight, research suggests the opposite. A 2008 study by Susan Swithers, PhD, and Terry Davidson, PhD, published in Behavioral Neuroscience (Vol. 122, No. 1), found that rats exposed to low-calorie sweeteners will eat more than rats exposed to calories coming from sugar.
Their theory, Brownell explained, is that the body has an anticipatory metabolic process that prepares for incoming calories when a person senses something sweet. But when that treat delivers fewer calories than expected via artificial sweeteners, the body is fooled. It may stay in that calorie-ready state and that creates excess hunger, Brownell said.
The best bet with so many unknowns? "Just drink water," said Brownell.
If psychologists can put more research along these lines in policy-makers' hands, they have the potential to change the nation's diet and reverse rising obesity rates, said Brownell.
Leading by example, Brownell and fellow researchers at Yale's Rudd Center for Food Policy and Obesity have dubbed their work "strategic science." Each study they pursue begins with the same questions: "What will it take to change public opinion, to change the way the law is interpreted, to change the way politicians look at an issue?" said Brownell.
Strategic science also includes input from people outside of academe.
"I never meet a senator or a congressman or an attorney general without asking, 'If there is only one piece of science that will help you make your case or help convince you that this is an important issue, or to convince your colleagues to put this on the map, what would that be?'" he said.
The Rudd Center also brought a lawyer on board to brief them on the legal aspects of their work -- such as what kind of marketing is considered misleading, unfair or deceptive and therefore not protected by the First Amendment.
Changing the law to make wholesome eating easier for all, Brownell said, is the key to a healthier nation.