In this article:
- Highlights of Studies
- How Body Mass Index is Determined
- Possible Reasons Children with ADHD are Overweight
- What Parents Can Do to Help
Do children with ADHD have a higher prevalence of being overweight? There have been several studies trying to answer this question over the past several years, but the answer is still not clear. While at least two studies have shown an association between ADHD and obesity, other studies have shown no statistically relevant difference in being overweight between children with ADHD and the general population.
Highlights of some of the studies:
- A study published in the July 2008 issue of Pediatrics indicated that children with ADHD, who were not taking medication had a 1.5 higher risk of being overweight and children with ADHD, who were taking medication, had a 1.6 risk of being overweight. Overall, about one in five children with ADHD were overweight, but Dr. David Katz (Director of Prevention Research Center at Yale University School of Medicine) points out that although there is a higher risk, the level of risk may not be clinically relevant.
- An Israeli study, completed in 2005, showed that one half of obese children in the study had ADHD. One half of those with obesity had not previously been diagnosed with ADHD.
- A study published in the International Journal of Obesity (2004) indicated that the children with ADHD participating in the study had a higher average BMI score than the reference value for children without ADHD. The study showed 19.6 percent of the children were over the 90 percent BMI and 7.2 percent were over the 97th percentile.
- A study published in 2005 by BMC Pediatrics showed no statistical difference between children with ADHD and children without ADHD as far as being overweight. 
How is Overweight/Obesity Determined?
The Body Mass Index (BMI) is used to determine if a person is overweight. To find out if your child would be considered overweight or obese, divide their weight by their height, in inches. If your answer is:
- Below 25 your child would not considered to be overweight
- Between 25 and 29.9 your child would be considered in the 85th percentile of BMI
- Over 30 your child would be considered to be in the 95th percentile of BMI
A complete medical evaluation is recommended for children in the 95th percentile. These children may have a higher risk of elevated blood pressure and other illnesses and may have a higher risk of remaining overweight into adulthood.
Possible Reasons for Children with ADHD Being Overweight
There are a few theories on why children with ADHD may be at risk for being overweight.
- Excessive eating, or overeating, may be the result of stresses felt by a child with ADHD. Food may become the comfort or may be a way for children to make themselves feel better.
- Impulsivity can contribute to overeating, with children with ADHD lacking the controls to stop eating or avoid eating sweets, junk food or stopping eating when they are full.
- Parents of children are more apt to have ADHD and, if undiagnosed, may not have the organizational skills to follow up on proper diet and nutrition.
- Since obesity is more common in lower-income families, children with ADHD and their parents from these backgrounds may be more apt to be undiagnosed and untreated, allowing for both the parents and children to succumb to impulsiveness of overeating.
It is, however, premature to look for causes, when a definitive link between ADHD and obesity has yet to be determined.