Young adults with a history of symptoms of attention-deficit hyperactivity disorder (ADHD) may be more likely than their peers to be obese, a new study suggests.
The findings, from a study of more than 11,000 young U.S. adults followed since adolescence, do not prove that ADHD by itself raises the risk of obesity. But they are in line with a number of smaller, previous studies finding that both children and adults with ADHD have a higher obesity rate than those without the disorder.
The reasons are not yet certain. But it’s biologically plausible, researchers say, that the impulsive behavior that commonly marks ADHD would be related to excess weight gain.
According to the Centers for Disease Control and Prevention, between three and seven percent of school-aged kids in the U.S. suffer from ADHD.
In the new study, researchers at Duke University in Durham, North Carolina, examined data from 11,666 young U.S. adults taking part in a government health study begun in 1995, when the participants were in high school.
In 2001-2002, when participants were age 23, on average, they were surveyed on whether they’d had various ADHD-like symptoms between the ages of five and 12. They were followed up again six to seven years later, when their weight and other health and lifestyle factors were recorded.
Overall, the researchers found, young adults who said they’d had three or more ADHD-like symptoms during childhood had a higher rate of obesity than those who reported no such symptoms.
A history of hyperactivity or impulsive behavior—as opposed to problems with attention—was particularly related to obesity.