Abstract
This experimental study confirms that insomnia and especially early morning waking is associated with low body weight in anorexia nervosa. It extends the view that there is a relationship between reduced nutritional intake and consequent change in weight and sleep disturbance. This relationship was studied by comparison of certain sleep EEG parameters in a group of hospitalized anorexia nervosa patients before and after a regime of re-feeding to matched population mean weight on a ‘normal’ diet. At low body weights, the patients had less sleep and more restlessness, especially in the last 4 hr of the night. After weight gain, there was a significant increase in length of sleep and REM sleep. The implications of these results are discussed with particular reference to an association between various anabolic profiles and differing need for REM sleep.