Physical growth during middle childhood (ages 6-12) is slow but steady, with children gaining 2-3 inches and 5-7 pounds per year on average. Nutrition plays an important role in physical development, with proper nutrition linked to positive personality traits and undernutrition/malnutrition leading to physical, social, and cognitive difficulties. Rates of asthma have doubled since the 1980s. Around 2-5% of children experience depression, which can be treated through counseling or controversially with drugs. Other conditions like ADHD, learning disabilities, and sensory impairments also impact around 5% of children.