The Causes of ADHD

What Are the Possible Causes of ADHD?

There are many theories for what specifically causes ADHD. Many people affected by the condition have asked doctors and researchers whether ADHD may have something to do with what they eat or even with watching too much TV. The fact is there is no evidence that either factor contributes to ADHD.

The exact cause of ADHD is unknown, but researchers believe this condition may be caused by one or more of the following factors.

Brain Chemistry

ADHD is thought to be caused by an imbalance of two chemical messengers, called neurotransmitters, in the brain. Researchers think these two chemicals may play an important role in ADHD. These are noradrenaline and dopamine.


Research suggests ADHD can be seen across generations. According to studies, the relatives of people with ADHD are six times more likely to develop the condition than people without a family history. In fact, over three quarters or 75% of ADHD cases can be attributed to genetics. This does not mean that all children in a family will have the condition. You can track ADHD symptoms in your family by completing your family tree.     


Certain external factors, such as smoking during pregnancy or complications during pregnancy, delivery, or infancy, may contribute to ADHD.