Eating Disorders Lay Summaries

2013

Low maternal vitamin D increases the risk of eating disorders in offspring

Keywords: eating disorders, pregnancy, risk factors, vitamin D, adolescent

What is already known about this subject:

  • A mother’s vitamin D levels during pregnancy have been shown to affect her child’s health, and are thought to be important in brain development.
  • Research suggests that being born at certain times of year increases an individual’s risk of developing an eating disorder. This may be related to fluctuations in maternal vitamin D levels due to varying sun exposure throughout the year.
  • It is not known if vitamin D levels are responsible for the observed links between season of birth and risk of eating disorders.

What this Raine study adds:

  • Maternal vitamin D levels in blood samples collected at 18 weeks gestation together with season of birth and eating disorder data in offspring at 14, 17 and 20 years of age demonstrated that low maternal vitamin D during pregnancy was related to an increased risk of eating disorders in female offspring during adolescence.
  • Differences in eating disorder risk with season of birth were explained by differences in maternal vitamin D levels.
  • More research is needed to further clarify the role of maternal vitamin D in the development of eating disorders.

Allen, K. L., Byrne, S. M., Kusel, M. M. H., Hart, P. H., & Whitehouse, A. J. O. (2013). Maternal vitamin D levels during pregnancy and offspring eating disorder risk in adolescence. The International Journal of Eating Disorders, 46, 669-76. doi:10.1002/eat.22147. [publink]

Screening for adolescents at risk of persistent eating disorders: purging and behaviour problems in early and mid-adolescence predict eating disorder persistence

Keywords: adolescent, binge eating, eating disorders, purging, course, outcome

What is already known about this subject:

  • Up to 15% of women experience an eating disorder during their lifetime.
  • Little is known about the natural course of eating disorders in the community, as most data comes from ‘clinical’ samples of patients seeking treatment.
  • It is also not yet clear which factors differentiate between individuals whose eating disorders remit (get better) or persist.

What this Raine study adds:

  • Data from eating disorder questionnaires at 14, 17 and 20 in Raine participants showed that those who exhibited behavioural difficulties in early adolescence and purging in middle adolescence were more likely to have an eating disorder that persisted at each follow up.
  • Participants who experienced a persistent eating disorder were less likely to complete high school and reported problems with anxiety and depression at 20 years of age.
  • Remission rates decreased with age: half of those with eating disorders at 14 had no eating disorder at 17 or 20, whereas only 29% of those with eating disorders at 17 had no eating disorder at 20.
  • Screening for eating disorders in the community and the provision of tailored interventions to adolescents at risk may minimise the risk of long-term eating disorders.

Allen, K. L., Byrne, S. M., Oddy, W. H., & Crosby, R. D. (2013). Early onset binge eating and purging eating disorders: Course and outcome in a population-based study of adolescents. Journal of Abnormal Child Psychology, 41, 1083-1096. doi:10.1007/s10802-013-9747-7. [publink]

Higher prevalence of eating disorder diagnoses using new diagnostic criteria

Keywords: adolescent, depression, eating disorders, prevalence, diagnostic criteria

What is already known about this subject:

  • Eating disorders most commonly develop during adolescence.
  • The diagnosis and classification of eating disorders has recently been updated, with the new criteria less likely to diagnose an ‘unspecified’ eating disorder. This is likely to increase the relative prevalence of specific eating disorder diagnoses, and so new prevalence rates need to be established.

What this Raine study adds:

  • Eating disorder data from self-report questionnaires completed by Raine participants at 14, 17 and 20 years of age were compared using diagnostic criteria from the current and previous editions of the Diagnostic and Statistical Manual of Mental Health Disorders (DSM-5 vs DSM-IV-TR). Eating disorder prevalence rates were higher when using the new criteria at all time points in females, and at 17 years of age in males.
  • A high cross-over from binge eating disorder to bulimia nervosa was observed using the DSM-5, and binge eating disorder or purging disorder in early adolescence predicted bulimia nervosa in later adolescence.
  • All of the eating disorder diagnoses (regardless of the diagnostic criteria used) were associated with psychological distress, showing that the eating disorders previously included in the ‘unspecified’ diagnostic category are also clinically important.

Allen, K. L., Byrne, S. M., Oddy, W. H., & Crosby, R. D. (2013). DSM-IV-TR and DSM-5 eating disorders in adolescents: prevalence, stability, and psychosocial correlates in a population-based sample of male and female adolescents. Journal of Abnormal Psychology, 122(3), 720-32. doi:10.1037/a0034004. [publink]

Low fatty acid intake is associated with depression in adolescents with eating disorders

Keywords: adolescent, depression, eating disorders, fatty acids, nutrition

What is already known about this subject:

  • Eating disorders are serious mental illnesses and affect both men and women.
  • Little is known about the dietary intake and nutritional status of people in the community who have eating disorders.
  • Depression is common in individuals with eating disorders, and it is thought that inadequate dietary intake of fatty acids may play a role.

What this Raine study adds:

  • Dietary intake, eating disorder symptoms and depression data from questionnaires completed by female Raine participants at 17 years of age revealed that adolescents with an eating disorder consumed less dietary fat (including saturated fat, omega-6 fatty acids, starch, vitamin A and vitamin E) than adolescents without an eating disorder.
  • Adolescents with an eating disorder and depression also consumed less fatty acids (omega-3 and omega-6) than adolescents with an eating disorder but who did not have depression.
  • Fatty acid supplementation may be useful in adolescents with eating disorders.

Allen, K. L., Mori, T. A., Beilin, L., Byrne, S. M., Hickling, S., & Oddy, W. H. (2013). Dietary intake in population-based adolescents: Support for a relationship between eating disorder symptoms, low fatty acid intake and depressive symptoms. Journal of Human Nutrition and Dietetics, 26, 459-469. doi:10.1111/jhn.12024. [publink]

2012

Adolescents with eating disorders have detectable differences in thinking skills

Keywords: eating disorders, cognitive function, adolescent

What is already known about this subject:

  • Problems with cognitive function (‘thinking skills’) have been identified in individuals with eating disorders such as anorexia and bulimia.
  • There is weak but increasing evidence to suggest that eating disorders are associated with difficulties in ‘big picture’ thinking (or a tendency to focus on details) and being able to switch between tasks (mental inflexibility).
  • Most of the existing data has been collected in young adults, and it is not yet known if the differences also exist in adolescents with eating disorders.

What this Raine study adds:

  • Cognitive testing and eating disorder data in a subset of Raine participants at 17 years of age showed that adolescents with eating disorders performed less well than those without eating disorders on tests of ‘big picture’ thinking and mental flexibility.
  • Adolescents with eating disorders scored better on tests of attention.
  • It is now important to extend this research in order to determine whether cognitive difficulties are present before the onset of eating disorders in order to develop new prevention and treatment strategies.

Allen KL, Byrne SM, Hii H, van Eekelen A, Mattes E, Foster JK. Neurocognitive functioning in adolescents with eating disorders: A population-based study. Cogn Neuropsychiatry. 2012 Jul 17;18(5):355-75. [publink]