Eating disorders have increased in young children and is higher than previously thought, a new study found.
But it affects equally boys and girls and it is only after puberty does a clear sex difference emerge with girls more prone to bulimia, binge eating and other eating disorders.
Anorexia affected equally boys and girls
The frequency of eating disorders in children aged nine and ten was found to be as higher than previous estimates, at 1.4 per cent as they suffer other psychiatric illnesses.
Sex differences only emerged when children become teenagers, with nearly all disorders more common in teenage girls than boys.
The study comes after research that showed having more than one psychiatric disorder is now more common in children than teenagers.
More than 1.6 million people in the UK are estimated to suffer from eating disorders such as anorexia, bulimia and binge-eating.
But the real number is likely to be higher because there is a “huge level of unmet need in the community”, according to charities.
Anorexia most commonly affects girls and women, although it has become more common in boys and men in recent years.
On average, the condition first develops at around the age of 16 to 17.
Recent studies suggest that as many as eight per cent of women have bulimia at some stage in their life and an estimated quarter of British people struggling with eating disorders could be male.
To reach the new findings, researchers studied the frequency of eating disorders in more than 4,500 nine to ten-year-old Americans taking part in the Adolescent Brain Cognitive Development (ABCD) study in 2016 and 2017.
Eating disorder diagnoses were determined using a parent or guardian.
Lead author Associate Professor of psychology Aaron Blashill at San Diego State University said: “Eating disorders are associated with significant morbidity and mortality.
“The prevalence of early-onset eating disorders has increased in the past several decades,with younger children more likely than adolescents to experience psychiatric comorbidity.”
Comorbidity is the presence of one more psychiatric disorders.
He added a previous single nationally representative study found the 12-month prevalence rates of eating disorders among children aged eight to 15 years found 0.1 per cent total for children aged eight to 11 years, with 0.3 per cent for girls and 0.1 per cent for boys aged eight to 15 years old.
But he said: “This previous study used Diagnostic and Statistical Manual of Mental Disorders criteria and did not report the prevalence of specific eating disorders diagnoses.
“The aims of the present study were to report the prevalence rates of anorexia nervosa, bulimia nervosa, binge eating disorder, and other specified feeding and eating disorders.”
The new study found eating disorders were higher than expected.
Prof Blashill said: “Across all eating disorder diagnoses, the overall frequency was 1.4 per cent with no significant differences between girls and boys in a nationally representative group of 4,500 children nine to 10 years old.
“The authors suggest sex differences in eating disorders may not emerge until later on in adolescence.”
The researchers found only 0.1 per cent of children in that age group suffered from anorexia, 0.6 suffered from binge-eating, while none at all suffered from bulimia.
Prof Blashill said: “In this group of children, the prevalence of anorexia nervosa was 0.1 per cent, there were no cases of bulimia nervosa, the frequency of binge-eating disorder was 0.6 per cent, and the prevalence of any other specified feeding and eating disorder diagnosis was 0.7 per cent.
“Significant sex differences were not found across eating disorders diagnoses.
“Similarly, past research with adolescents aged 13 to 18 years did not find sex differences in the prevalence of anorexia nervosa.
“However, differences emerged for bulimia nervos, binge eating dis-order, and subthreshold anorexia nervosa, with higher prevalence among girls.
“Taken together, sex differences in eating disorders may not emerge until adolescence.
“This is consistent with previous research demonstrating a lack of prepubertal sex differences in eating disorders, with elevated prevalence of eating disorders in girls during and after puberty.”
The study published in JAMA Pediatrics.
By Grainne Cuffe