Rotorua parents concerned their child may be suffering from an eating disorder should consult their family doctor, the Lakes District Health Board says.
"Anyone with health concerns should see their general practitioner and seek referral to a specialist as soon as possible,'' communications officer Shan Tapsell said.
Her comments follow research indicating doctors may be missing at-risk teenagers because of poor questioning about their weight-loss practices.
Eating disorders are classed as a mental illness by the Health Ministry. About 0.5 per cent of all Kiwis are estimated to suffer from the disease.
Ms Tapsell told The Daily Post eating disorder cases were relatively rare in the Lakes District and anyone who required specialised treatment was referred to the board's mental health service.
Most children and adolescents who were diagnosed with anorexia _ one of the most dangerous types of eating disorders _ were treated at the hospital's Maudsley Family Based Therapy programme.
Access to a residential regional service in Auckland was an option.
People diagnosed with anorexia suffer from a debilitating inability to eat. Their weight and body mass index levels plummet, causing serious health problems.
If left untreated, anorexia can also be fatal.
A University of Auckland study, which surveyed about 9000 high school students, found clinicians often failed to ask what methods young people used to control their weight.
``This may be due to uncertainty about which questions to ask, specifically around whether certain weight-loss strategies are healthier or unhealthy, or about what weight-loss behaviours are more likely to lead to adverse outcomes,'' the report said.
``Routine assessment of weight control strategies by clinicians are warranted, particularly for meal skipping and fasting for weight loss.''
Similar to autistic disorders, anorexia, bulimia and compulsive eating disorder are measured along an eating disorder spectrum.
This means symptoms vary widely among sufferers, as do known causes.
Typical signs of anorexia, for which the average age of onset is 17 years, include extremely low body weight and weakness.
Research has also indicated adolescents who suffer from anorexia are usually high achievers, involved in a variety of extra-curricular activities.
Contrary to popular belief, people who suffer from bulimia are usually a healthy weight. In many cases they can actually be over weight. Spotting people with bulimia is often more difficult as there are few physical signs of the disease. Visible signs include tooth erosion and calluses on a person's knuckles from constant vomiting.
The Auckland research also highlighted risky behaviour associated with weight control, which is often symptomatic of an eating disorder.
A 2009 Youth Risk Behaviour survey found participants attempting to control their weight through vomiting, starvation and diet pills ate fewer fruits and vegetables and more high-fat foods compared with those who were not dieting or using moderate weight-control strategies.
``Skipping meals is not an effective weight-loss strategy, as available research on successful weight-loss suggests that regular meal consumption, particularly breakfast, is important in weight maintenance,'' the researchers said.