There were 207 men with ADHD and 178 men without ADHD in the study. The subjects were matched for age, residence, and social class. The average age of ADHD diagnosis was eight years old. The average age at the study followup was 41 years old.
According to the study,
Lack of impulse control and poor planning skills were thought to contribute to the increased rate of obesity. Poor impulse control and poor planning can lead to unhealthy food choices and irregular eating. People with ADHD also tend to eat more quickly and eat when they are bored - factors that also may contribute to the higher rate of obesity. It would be interesting to see the rate of obstructive sleep apnea (OSA) in the group. There is a 20-30% rate of OSA in people with ADHD, and being overweight is one of the risk factors for having OSA (Youssef, et al., 2011). NYU Langone Medical Center (2013, May 20). Link between childhood ADHD and obesity revealed in first long-term study. ScienceDaily. Retrieved September 30, 2013, from http://www.sciencedaily.com/releases/2013/05/130520113925.htm ..., N.A., et al. (2011). Is obstructive sleep apnea associated with ADHD? Annals of Clinical Psychiatry, 23(3):213-224.
...on average, men with childhood ADHD had significantly higher BMI (30.1 vs. 27.6) and obesity rates (41.1 percent vs. 21.6 percent) than men without childhood ADHD.