ADHD: An Inflammatory Condition: The Link Between ADHD and Obesity

Barry Sears Ph.D.

Just as we appear powerless to reverse the epidemic of childhood obesity, the growing number of children with attention deficit hyperactivity disorder (ADHD) also is escalating. Might the two disorders be linked? I believe the answer is yes, if we look closer at the role of diet in the induction of inflammatory responses.

According to the Centers for Disease Control, greater than 9 percent of children in the United States suffer from ADHD (1). This is approximately half the percentage of children who are obese (2). I suggest that both conditions are related to increased inflammation induced by radical changes in the American diet during the past 40 years. To understand that statement, you first have to understand something about inflammation.

There two types of inflammation. The first type is classical inflammation that hurts. The second type is cellular inflammation that is below the perception of pain. Although this type of inflammation can be measured, it tends to be ignored since there is no associated pain. It is this type of cellular inflammation that causes disruption in the cellular signaling networks in individual cells that are required for the body's organs to run at peak efficiency. If the inflammation is in the fat cells, the result is increased accumulation of body fat. If the inflammation is in the brain cells, the result is increased neurological disorders, including ADHD.

The primary drugs used to treat ADHD are amphetamine derivatives that have the ability to stimulate dopamine receptors in the brain. We also know that children with ADHD have lower levels of long-chain omega-3 fatty acids in the blood compared to control children (3). So what is the connection? It turns out that omega-3 fatty acids in animal studies stimulate increased dopamine production as well as increasing the number of dopamine receptors (4). This begs the question whether or not simply increasing the blood levels of long-chain omega-3 fatty acids in the blood can have a significant positive impact in the treatment of ADHD. The answer is yes, as long as you are taking a therapeutic amount (5,6). If you take a placebo dose of any nutrient, you can expect a placebo result. Outside of these two studies, most others have used essentially placebo level doses of omega-3 fatty acids. The two studies that have indicated that high-dose omega-3 concentrates do demonstrate a statistically significant improvement in behavior in children with ADHD used between 7.5 and 10 grams per day of omega-3 fatty acids (5,6).