There are a number issues resulting from lack of sleep, many of which coincide with the physical effects of sleep deprivation.

Issues resulting from lack of sleep include exhaustion, fatigue, and lack of physical energy. This cascades into behavioral effects such as emotional instability, mood swings, stress, anger and pessimism. Studies completed in Australia have also shown that the physical effects of sleep deprivation are similar to those of a person driving with high blood alcohol content, including mental slowness, intermittent tiredness, muscular cramps and the inability to focus or concentrate.

Perhaps the most alarming physical effect is a cessation in the body's ability to properly metabolize glucose, thus resulting in physical effects similar to early-stage diabetes and aging.

There are a number of extreme physical effects/issues resulting from lack of sleep - people who have not slept for extended periods of time begin to show signs similar to those who have undergone physical overexertion - hernias and muscle fascia tears. The longer the period of sleep deprivation, the greater the physical signs become.