Diet hasn't been shown to cause attention-deficit/hyperactivity disorder (ADHD) in children. Additionally, diet alone can't account for the symptoms of ADHD. However, there's no denying that diet plays a crucial role in physical and mental health, especially for growing children.Children with ADHD have extra challenges. Fueling them with good, nutritious food goes a long way toward helping them cope and stay healthy.Far too many children aren't getting the vitamins, minerals, and fiber they need. All children require a diet rich in: vegetables, fruits, whole grains, protein, healthy fats, calcium-rich foods, among others.Such a diet may or may not improve symptoms of ADHD in children, but it will provide them a foundation for good health.