Children with ADHD may benefit from following healthy behaviors, new study suggests | EurekAlert! Science News:
Recommendations include getting no more than 1 to 2 hours of total screen time daily; getting at least 1 hour of physical activity daily; limiting consumption of sugar sweetened beverages; getting 9 to 11 hours of sleep per night; and consuming 7 to 10 cups of water daily, depending on age. Holton and Nigg created a lifestyle index to summarize the total number of healthy lifestyle behaviors adhered to by 184 children with ADHD as compared to a control group of 104 non-ADHD youth.
So kids with ADD don't have healthy behaviors, but I don't know if that necessarily means that the healthy behaviors improve ADD symptoms.