Factors that Don't Cause ADHD

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Over the years, a number of myths have developed concerning causes of ADHD. As one prominent ADHD expert has put it, "Some of these were originally founded in sound hypotheses but have since been disproved. Others are sheer falsehoods; there is not now and never has been any scientific support for them" (Barkley, 2000, p. 75). Chief among these unsubstantiated claims are food additives, sugar, and bad parenting.

Back in the 1970s, Benjamin Feingold, a pediatric allergist, introduced the theory that certain food additives caused hyperactivity in children (Feingold, 1975). Specifically, he claimed that such things as artificial food coloring, preservatives, and salicylates, which occur naturally in many foods, should be eliminated from the diets of children with ADHD. The Feingold diet is highly restrictive, because so many foods contain not only additives but relatively high levels of salicylates (e.g., olives, honey, avocados, cherries, grapefruit, apples, broccoli, and cucumbers, to name a few).

Although there are still proponents of the Feingold diet, research has long ago disproved it as of benefit for most children with ADHD (Kavale & Forness, 1983).

Sugar, too, has been implicated as a culprit in causing hyperactivity. However, careful research has demonstrated that sugar does not cause high levels of motor activity in most children (Wolraich, Wilson, & White, 1996). Where the mistaken notion that sugar causes hyperactivity may have gotten its start is from the frequent observation that children are hyperactive in situations where sweets are served. Parents and teachers often remark that young children's birthday parties are an occasion for high levels of motor activity and distractibility. They often point to the sugar in the cake or cookies as causing this hyperactivity when it's more likely that the unstructured and stimulating nature of the situation are the causes .

Although research has clearly shown that food products, whether it be food additives, salicylates, or sugar, are not causes of ADHD, we should be open to the possibility that some individuals may have a relatively small reaction to foods because of food allergies. However, the evidence is overwhelming that such reactions are, at most, extremely rare.

It is common for parents of children with ADHD to be targeted as the reason for their child's condition. Many people believe that overly lenient parenting and/or disorganized and dysfunctional family dynamics account for children's ADHD. This seems especially true of children with ADHD, Predominantly Hyperactive-Intensive Type. Shannon's mother has not experienced this, but the following quote from the mother of a child with ADHD, Predominantly Hyperactive-Impulsive Type, is instructive.

I don't know what it is about some people. I guess I can kind of understand it. Before we had Michael, I think I was guilty of the same thing. Whenever I saw a kid who was out of control in the supermarket, I'd immediately jump to the conclusion that his parents must be at fault. I just know that some folks, including some teachers, think we must have some kind of terribly disorganized family life or that we don't discipline him when he misbehaves. I wouldn't want to wish having a child with Michael's problems on anyone. But I do think it's usually parents who happen to be blessed with near-perfect children who think this way. If they were to have a child with ADHD, I think they'd quickly change their tune.

Sharon Irving, mother of a child with Predominantly Hyperactive-Impulsive Type ADHD

Some have observed that many parents of children with ADHD exhibit ADHD symptoms themselves. However, this may be explained by the fact, which we have already discussed, that ADHD is highly heritable (Barkley, 2000). One team of researchers (Biederman, Faraone, & Monuteaux, 2002), for example, compared the behavior of over 1,000 offspring from three groups of parents: (l) parents who currently displayed ADHD, (2) parents who had previously displayed ADHD but not longer did so, and (3) parents without ADHD. Children of parents with ADHD were much more likely to have ADHD. However, children's risk of having ADHD did not differ between parents who had persistent ADHD and those who did not have active ADHD symptoms during the child's lifetime. One interpretation of these results is that a child's being exposed to ADHD behavior in the parent does not put the child at as great a risk for having ADHD as does the fact of being genetically linked to a parent with ADHD.

In summarizing the research on parenting and ADHD, one authority has concluded:

All of this evidence makes it highly unlikely that any purely social cause, such as "bad parenting" or a disruptive, stressful home life, creates ADHD in the children of such families. Instead, the research suggests that children with ADHD can create stress for their parents and cause some disruption of family life. In cases where poor parenting and disruptive family life have some influence on children, it seems to be one of contributing to aggressive and defiant child behavior, not to ADHD. (Barkley, 2000, p. 81)