UF College Of Medicine Researchers Report Link Between Overeating, Obesity And Addiction
GAINESVILLE, Fla. — “Junk Food Junkie,” that novelty song from the ’70s, may contain more medical truth than anyone imagined.
University of Florida addiction researchers say mounting evidence suggests chronic overeating can be a form of substance abuse, and that illicit drugs snare users because they engage brain pathways associated with appetite and the enjoyment of food.
Four UF studies published in the current issue of the Journal of Addictive Diseases present new evidence linking overeating, obesity and addiction, and could have treatment implications for people struggling with weight problems, alcoholism or drug use, said Dr. Mark Gold, chief of addiction medicine at UF’s College of Medicine and co-author of three of the papers.
“What’s the difference between someone who’s lost control over alcohol and someone who’s lost control over good food?” asked Gold, who also is a distinguished professor of psychiatry at UF’s McKnight Brain Institute. “When you look at their brains and brain responses, the differences are not very significant.”
Gold, an early proponent of the food-as-drug model, said the medical community considered the idea radical a decade ago, but many addiction specialists now give it serious consideration. Advances in imaging technology, neurochemistry and other fields have enabled basic science researchers to map rodents’ brain pathways and show how food and drugs evoke similar responses. At the same time, clinical researchers such as Gold have begun investigating the relationship between food-seeking and drug-seeking behaviors in people.
“We’ve taken the position that overeating is in part due to food becoming more refined, more palatable, more hedonic,” Gold said. “Food might be the substance in a substance abuse disorder that we see today as obesity.”
Obesity is the second most common cause of premature death in the United States, and is predicted to overtake tobacco use as the No. 1 cause within a few years, he said. About 24 percent of U.S. adults aged 20 years and older are obese, according to estimates from a 2003 National Center for Health Statistics survey.
The UF research suggests obesity may be a hidden hazard for people starting on the road to sobriety.
Treatment for drug or alcohol addiction may be more likely to succeed if it includes a plan for a healthy diet and regular exercise, according to one of the papers Gold co-authored. A case-history review of 75 teenagers undergoing long-term residential drug treatment showed they gained an average of 11 pounds during the first 60 days, a change researchers believe may have happened to compensate for the loss of brain stimulation when drug use ended. The patients were monitored with urine screens to ensure they remained drug-free during treatment.
“Theoretically, the (finding) has the implication that says there is a push-pull – if the drugs are there, eating goes away; if drugs are gone, eating increases,” Gold said.
Similar supportive data came from a UF study in the journal that correlated obesity and self-reported alcohol use in female patients undergoing weight-loss treatment. The more obese the patient, the less likely she was to drink alcohol, said UF addiction medicine expert Dr. William Jacobs, who helped review the files of about 300 women 16 to 79.
“The impression that a lot of folks have, including health-care providers, is that obese patients sit around and drink, that’s part of the reason they’re obese. And this has shown exactly the opposite,” said Jacobs, an assistant professor of psychiatry and anesthesiology. “Eating is probably competing and substituting for alcohol in the brain in the reward pathways in these patients.”
Future research could help scientists determine which patients would benefit by being treated as food addicts, Jacobs said. Some people overeat because they suffer from conditions such as depression or diabetes, and successful treatment for the underlying cause may reduce their eating to healthier levels.
Because the mechanisms that cause the urge to eat and the urge to abuse alcohol or drugs appear to overlap, researchers may one day be able to design medications that would reduce the desire for both activities, said Satya Kalra, a UF professor of neuroscience. In the meantime, researchers say, exercise and a healthy diet are the best prescription for weight loss and weight maintenance.
In the journal, Kalra and his wife Pushpa Kalra, a UF professor of physiology and functional genomics, wrote an article that reviewed existing research regarding the pathways regulating appetite and drug craving in a part of the brain called the hypothalamus.
“It appears there is a commonality of the signaling that is associated with appetite or the urge to eat as well as drug craving,” Satya Kalra said.
The food-as-drug model is “extremely important” and opens up many new areas of research and treatment, said Dr. Robert L. DuPont, a former White House drug czar and current president of the Institute for Behavior and Health, a nonprofit research organization in Rockville, Md.
“I think it also helps in the public understanding of both eating disorders and addiction to alcohol and other drugs,” DuPont said. “Dr. Gold has pioneered in this area, and it’s a very significant professional contribution.”