Humans are designed to be nose breathers, but somewhere along the way, nose breathing can change to mouth breathing and reduced oxygen absorption. Adequate oxygen levels lead to regenerative sleep and the release of human growth hormone. Mouth breathing leads to lower oxygen absorption levels, poor sleep, and misdiagnosis of children with attention deficit hyperactivity disorder (ADHD). Normal nasal breathing involves the tongue being up, teeth apart, and lips together. In children, the tongue up during rest and swallowing provides the necessary stimulus for adequate palatal development. The tongue position associated with mouth breathing leads to compromised jaw development and a restricted airway. Mouth breathing is a predictor of sleep apnea, long face syndrome, and other developmental and sleep-related problems.