Eating a balanced diet is key to staving off disease and maintaining a healthy weight, but according to a team of researchers from King’s College, London, it could even influence ADHD risk in unborn babies. More than six million children have gone on to develop attention deficit hyperactivity disorder (ADHD), one of the most common behavioral disorders in children, causing problems with attention, impulsive behavior, and an overactive demeanor. New findings reveal that the onset of the disorder may begin in the womb.

Researchers recruited 83 children who exhibited early-onset conduct problems, which is one of the first signs of ADHD, and a second group of 81 children who had relatively normal levels of conduct for their age. After observing the children’s behavior, researchers analyzed their mothers’ nutrition along with the children’s DNA to see if there were any changes in the brain. They found mothers who had eaten high quantities of sugar, fat, and processed foods throughout their pregnancy were the most likely to give birth to children with conduct problems.

But it went beyond just how the children behaved. Researchers found a mother’s diet during pregnancy had the power to influence epigenetic changes in the baby’s brain. These type of changes affect the genetic code itself, switching genes on and off in a person. In the case of ADHD, a highly processed diet laced with sugar and fat switched on the IGF2 gene, which causes the fetal development of ADHD in the brain. The higher the IGF2 gene was expressed, the higher the child’s ADHD symptoms were between the ages of 7 and 13.  

“Our finding that poor prenatal nutrition was associated with higher IGF2 methylation highlights the critical importance of a healthy diet during pregnancy, said the study’s co-author Dr. Edward Barker, ADHD expert and researcher at King's College, in a statement. “Promoting a healthy prenatal diet may ultimately lower ADHD symptoms and conduct problems in children. This is encouraging given that nutritional and epigenetic risk factors can be altered.”

Parker recommends pregnant women to stay away from processed foods and treats that are high in fat and sugar in order to protect their unborn baby from such genetic changes in the brain. Instead, women can turn to nutrient-packed fats, such as omega-3 fatty acids from fish, walnuts, and lean meats like chicken and turkey, which he says are “extremely important for neural development.”

Moving forward, Parker concluded: “We already know that nutritional supplements for children can lead to lower ADHD and conduct problems, so it will be important for future research to examine the role of epigenetic changes in this process.”

The ADHD rate among children in the United States has increased significantly since 2003. Read here.

Source: Parker ED, Rijlaarsdam J, Cecil CM, et al. Prenatal unhealthy diet, insulin-like growth factor 2 gene (IGF2) methylation, and attention deficit hyperactivity disorder symptoms in youth with early-onset conduct problems . Journal of Child Psychology and Psychiatry. 2016.