The most common medications used to treat ADHD are stimulants, which doctors believe balance excitatory chemicals in the brain and even out nerve firings so they are less chaotic. Stimulants include amphetamines, which for decades have been used as a metabolism booster to help the body burn calories faster; the connection between ADHD meds and increased body mass has puzzled scientists for quite some time.
Dr. Brian Schwartz, professor of environmental-health sciences, epidemiology, and medicine at Johns Hopkins, along with his colleagues, compared how BMI changed when children diagnosed with ADHD were treated with stimulants. They studied a group of 163,000 children ages three to 18 over a period of up to 13 years. While taking medication, these kids had BMIs slightly below that of their peers — an expected result, since stimulants can inhibit growth.
BMI changes that occurred after the children stopped taking their medication, however, were surprising. By age 13, those who had previously taken the drugs started to put on weight and their BMI growth curved dramatically upward. Schwartz writes in the journal Pediatrics that these findings indicate that long after children have stopped taking medications such as Ritalin, Adderall, and Concerta, their bodies may still be feeling the effects of the drug, and the medications appear to alter the BMI trajectory for a long period of time.
It’s possible the changes in brain chemicals caused by ADHD medications could reset and prime young bodies for obesity by disrupting normal appetite signals and calorie-burning processes. More studies will be needed to confirm this theory.