“ADHD, it’s just a couple of symptoms — it’s not a disease,” the Dutch researcher tells All Things Considered weekend host Guy Raz. The way we think about — and treat — these behaviors is wrong, Pelsser says. “There is a paradigm shift needed. If a child is diagnosed ADHD, we should say, ‘OK, we have got those symptoms, now let’s start looking for a cause.’ ”

According to Pelsser, 64 percent of children diagnosed with ADHD are actually experiencing a hypersensitivity to food. Researchers determined that by starting kids on a very elaborate diet, then restricting it over a few weeks’ time.