A syndrome characterised by the loss of at least a quarter of a person's normal body weight; by fear of normal weight; and, in women, by AMENORRHOEA. An individual's body image may be distorted so that the sufferer cannot judge real weight and wants to diet even when already very thin.

Anorexia nervosa usually begins in adolescence, affecting about 1–2 per cent of teenagers and college students: it is 20 times more common among women than men. Up to 10 per cent of sufferers’ sisters also have the syndrome. Anorexia may be linked with episodes of bulimia (see below).

The symptoms result from secretive self-starvation, usually with excessive exercise, self-induced vomiting, and misuse of laxatives. An anorexic (or anorectic) person may wear layers of baggy clothes to keep warm and to hide the figure. Starvation can cause serious problems such as ANAEMIA, low blood pressure, slow heart rate, swollen ankles, and OSTEOPOROSIS. Sudden death from heart ARRHYTHMIA may occur, particularly if the sufferer misuses DIURETICS to lose weight, which depletes the body's level of potassium.

There is probably no single cause of anorexia nervosa. Social pressure to be thin seems to be an important factor and other psychological theories include fear of adulthood and fear of losing parents’ attention.

Treatment starts by ruling out other illnesses causing similar signs and symptoms. These include DEPRESSION and disorders of the bowel, PITUITARY GLAND, THYROID GLAND, and OVARIES.

If the diagnosis is clearly anorexia nervosa, the general practitioner may refer the sufferer to a psychiatrist or psychologist. Moderately ill sufferers can be treated by COGNITIVE BEHAVIOUR THERAPY. A simple form of this is to agree targets for daily calorie intake and for acceptable body weight. The sufferer and the therapist (the general practitioner or a member of the psychiatric team) then monitor progress towards both targets by keeping a diary of food intake and measuring weight regularly. Counselling or more intensely personal PSYCHOTHERAPY may help too. Severe life-threatening complications will need urgent medical treatment in hospital, including rehydration and feeding using a nasogastric tube or an intravenous drip.

About half of anorectic sufferers recover fully within four years, a quarter improve, and a quarter remain severely underweight with (in the case of women) menstrual abnormalities. Recovery after ten years is rare and about 3 per cent die within that period, half by suicide.

is a syndrome characterised by binge eating, self-induced vomiting and laxative misuse, and fear of fatness. There is some overlap between anorexia nervosa and bulimia but, unlike the former, bulimia may start at any age from adolescence to 40 and is probably more directly linked with ordinary dieting. Bulimic sufferers say that, although they feel depressed and guilty after binges, the ‘buzz’ and relief after vomiting and purging are addictive. They often respond well to cognitive behaviour therapy.

Bulimia nervosa does not necessarily cause weight loss because the binges – for example of a loaf of bread, a packet of cereal, and several cans of cold baked beans at one sitting – are cancelled out by purging, by self-induced vomiting and by brief episodes of starvation. The full syndrome has been found in about 1 per cent of women but mild forms may be much more common. In one survey of female college students, 13 per cent admitted to having had bulimic symptoms.

Bulimia nervosa rarely leads to serious physical illness or death. However, repeated vomiting can cause oesophageal burns, salivary gland infections, small tears in the stomach, and occasionally dehydration and chemical imbalances in the blood. Inducing vomiting using fingers may produce two tell-tale signs – bite marks on the knuckles and rotten, pitted teeth.