A chronic pattern of delayed sleep is common in around 80% of adults with ADHD. This results in sleep debt that increases the severity of ADHD and mood symptoms, as well as jetlag-like physical complaints. Chronic sleep debt is associated with several chronic diseases, including obesity, diabetes, cardiovascular disease, and cancer. It also impacts executive function skills, including the ability to organize, to make decisions, etc. Late sleep can be treated with sleep hygiene, melatonin at night and/or light therapy in the early morning. This may be beneficial for daily functioning, reduce severity of ADHD, and improve mood as well as health in the long term.