Bulimia Nervosa is an eating disorder that affects around 1% of females in their mid-teens/late 20s. Sufferers get overwhelming urges to binge on food and then, to avoid gaining weight, they purge what they've eaten by throwing up, taking laxatives, over-exercising, or all three. It's difficult to spot bulimia, as it doesn't necessarily lead to weight loss, and many sufferers confine their activities to their own home. Also, bulimia can come and go - it isn't necessarily permanent.

Physically, bulimia can lead to:

• Bad skin
• Irregular periods
• Exhaustion
• Damage to the throat and tooth decay caused by frequent vomiting

In the long term, a lack of nutrients can affect how internal organs work, and some sufferers have died of heart attacks, though this is rare.

Obvious signs of bulimia include sneaking off to the loo to vomit after eating, secrecy, mood swings and fluctuating weight.