Verified by Causes and Risk Factors
The causes of ADHD are not fully understood. As with other mental health and behavioral disorders, genes likely play a role, but recent research also implicates exposure to environmental toxins such as pesticides or lead, as well as prenatal cigarette smoking or alcohol intake. The belief that eating too much sugar causes the condition has not held up in research, though refined sugar may exacerbate hyperactive behavior in certain cases.
“Poor parenting” is not to blame for ADHD, but parenting styles and strategies can have an effect on children's self-regulating abilities. Children who are exposed to inconsistent discipline, or who suffer from neglect, may find it more challenging to rein in their impulses or direct their attention later on.
On This Page
Some studies have found an association between increased amounts of screen time early in life and a heightened risk of ADHD later on. But such findings are correlational, and do not show a causal link between screen time and attentional challenges. Some experts have suggested that it may be that those with attention challenges are naturally more drawn to screens than their counterparts. The American Academy of Pediatrics recommends that children under the age of 2 avoid screens whenever possible, regardless of their attentional capacities.
It is a popular belief that refined sugar causes hyperactivity or may even be to blame for ADHD itself. But evidence on the link between sugar and symptoms of ADHD has been mixed. Some research shows that hyperactive behavior does increase after eating refined sugar, while others have shown no difference in children’s behavior when they consume sugar versus a placebo. Some experts speculate that some children—with or without ADHD—may simply be more sensitive to sugar than others.
According to the DSM, which specifically requires that symptoms start before age 12, no. But many adults with ADHD report that they did not have symptoms in childhood, and some research has identified a number of clinical cases—including several longitudinal studies that followed children to adulthood—where ADHD symptoms did appear to first emerge in adulthood. Whether those cases were simply missed in childhood, or whether they’re the result of another mental health condition with similar symptom presentation, remains up for debate.
ADHD has long been perceived as a childhood disorder, and it’s true that some children with ADHD report no longer struggling with symptoms as adults. But in the majority of cases—as many as 60 percent, according to some estimates—symptoms will persist into adulthood. Unfortunately, adults who continue to grapple with symptoms of inattention or hyperactivity may avoid seeking treatment due to the incorrect assumption that they should have “grown out” of their ADHD.
Boys are certainly more likely to be diagnosed with ADHD than girls; the CDC reports that 12.9 percent of American boys between 2 and 17 have been diagnosed with ADHD, compared to 5.6 percent of girls. However, evidence suggests that because girls are more likely to display inattentive symptoms—or exhibit hyperactivity in less disruptive ways than boys do—they may be more likely to have their symptoms overlooked.
While some children do appear to “grow out” of their ADHD symptoms—in that they seem to struggle significantly less with symptoms as they age—there is no evidence that the disorder can be cured. Treatment, whether medical or behavioral, can help an individual manage their impairments, but it does not make the underlying causes of inattention or hyperactivity disappear. And even among children who “outgrow” symptoms, early developmental delays and academic setbacks may create enduring problems.
