Almost one in 10 girls have taken diet pills, weight loss supplements or laxatives in the past year, according to a study.
Research published in the JAMA Network Open found diet pills were the weight-loss product used most frequently by adolescents, followed by laxatives and diuretics.
Overall, just over one in 20 boys and girls had taken non-prescription diet aids in their lifetime, the study found, with girls more likely to take them.
The round-up of 90 studies was on 604,552 children aged 18 or under.
It included research from Europe, including more than 8,000 youngsters in the UK, together with data from North America, the Caribbean and Asia.
Overall, use of non-prescription weight-loss products by children of both sexes was 5.3 per cent.
However, when boys and girls known to be at greater risk of using diet pills was excluded (such as those with substance abuse and known eating disorders), this ranged from 2 per cent in the past week to 8.9 per cent in their lifetime.
The authors, led by the School of Public and Preventive Health at Monash University in Melbourne, said: “Non-prescribed weight-loss products in children are not medically recommended for healthy weight maintenance as they do not work, are dangerous, are associated with unhealthful weight gain in adulthood and increase the risk of being diagnosed with an eating disorder within several years of onset of use.
“Furthermore, childhood use of non-prescribed weight-loss products has been associated with low self-esteem, depression, poor nutritional intake and substance use.”
The researchers said girls were more likely than boys to use diet pills and weight-loss aids at all time points (past week, past month, past year and lifetime).
They added: “This is a public-health concern because correlates between use of weight-loss products have been found with girls who have a low self-esteem, parental influence to lose weight or parental dissatisfaction with weight, self-body dissatisfaction, peer groups who value thinness, and media or social media influences promoting unrealistic beauty standards.”
Tom Quinn, director of external affairs at the eating disorder charity Beat, told the PA news agency that unprescribed medications worsen eating disorder behaviours and make recovery more difficult.
He said teenagers and young people were taking diet pills without knowing the dangerous side effects.
He added: “We’re incredibly saddened and alarmed that so many children and young people have been able to access diet pills and laxatives.
“There’s an enormous pressure on young people to lose weight, and we often hear from people who are struggling with low self-esteem and body image as part of their eating disorder.
“Weight-loss medications are very dangerous, especially if taken without a prescription, but the promise of ‘quick results’ is often very attractive to people with eating disorders even if it harms their health.
“There must be stricter laws to ensure that weight-loss products are never sold to people with or vulnerable to an eating disorder.
“We also urge healthcare professionals to raise awareness of the dangers of weight-loss medications, including with under-18s, and to signpost to eating disorder support.” – PA