Attention deficit hyperactivity disorder (ADHD) is a neurobehavioral disorder. That is, ADHD affects the way a person’s brain processes information. It influences behavior as a result.
Approximately 5 percent of children in the United States have ADHD according to the Centers for Disease Control and Prevention (CDC).
The exact cause of this condition is unknown. Researchers believe that genetics, nutrition, central nervous system problems during development, and other factors play a significant role according to the Mayo Clinic.
There is strong evidence that a person’s genes influence ADHD. Researchers have found that ADHD runs in families in twin and family studies. It’s been found to affect close relatives of people with ADHD. You and your siblings are more likely to have ADHD if your mother or father has it.
No one has yet been able to find exactly which genes influence ADHD. Many studies have examined whether a connection exists between ADHD and the DRD4 gene. Preliminary research indicates that this gene affects dopamine receptors in the brain. Some people with ADHD have a variation of this gene. This has led many experts to believe that it may play a role in the development of the condition. There is likely more than one gene responsible for ADHD.
It’s important to note that ADHD has been diagnosed in individuals who have no family history of the condition. A person’s environment and a combination of other factors can also influence whether or not you develop this disorder.
Many researchers believe there may be a connection between ADHD and certain common neurotoxic chemicals, namely lead and some pesticides. Lead exposure in children may affect the level of education they achieve. It’s also potentially associated with inattention, hyperactivity, and impulsivity.
Exposure to organophosphate pesticides may also be linked to ADHD. These pesticides are chemicals sprayed on lawns and agricultural products. Organophosphates potentially have adverse effects on children’s neurodevelopment according to a 2016 study.
Nutrition and symptoms
There is no concrete evidence that food dyes and preservatives may cause hyperactivity in some children according to the Mayo Clinic. Foods with artificial coloring include most processed and packaged snack foods. Sodium benzoate preservative is found in fruit pies, jams, soft drinks, and relishes. Researchers haven’t determined whether these ingredients influence ADHD.
Smoking and alcohol
Perhaps the strongest link between the environment and ADHD occurs before a child is born. Prenatal exposure to smoking is associated with the behaviors of children with ADHD according to the CDC.
Children who were exposed to alcohol and drugs while in the womb are more likely to have ADHD according to a 2012 study.
There are many myths about what causes ADHD. Research has found no evidence that ADHD is caused by:
- consuming excessive amounts of sugar
- watching TV
- playing video game
- poor parenting
These factors can potentially worsen ADHD symptoms. None of these factors have been proven to directly cause ADHD.