title: Examining the relationship between pubertal stage, adolescent health behaviours and stress.
abstract: BACKGROUND
  This paper examines the associations between puberty and three important health behaviours (smoking, food intake and exercise) and explores whether these associations are mediated by puberty's relationship to stress and psychological difficulties.
  
  
  METHODS
  Data were taken from the first year of the ongoing, 5-year, Health and Behaviours in Teenagers Study (HABITS). This is a school-based study set in 36 schools in London. In the first year of the study, 4320 students (2578 boys, 1742 girls) in their first year of secondary education took part.
  
  
  RESULTS
  Among girls, being more pubertally advanced was associated with a greater likelihood of having tried smoking. Among boys, being more pubertally advanced was associated with a greater likelihood of having tried smoking, a higher intake of high-fat food and higher levels of exercise. More pubertally advanced girls experienced more stress but not more psychological difficulties. There were no associations between puberty and either stress or psychological difficulties in boys. Stress and psychological difficulties were associated with health behaviours in girls and boys, but neither of these factors mediated the relationship between pubertal stage and health behaviours found in girls.
  
  
  CONCLUSIONS
  These results suggest that the onset of puberty has a marked effect on the development of health behaviours. Puberty was related to an acceleration of the development of unhealthy behaviours, except for exercise behaviour in boys, where advanced puberty was associated with more exercise. These changes were unrelated to adolescent issues of stress and a causal explanation for these associations must be sought elsewhere.
authors.affiliation: Cancer Research UK Health Behaviour Unit, Department of Epidemiology and Public Health, University College London.
authors.forename: A E
authors.initials: AE
authors.lastname: Simon
authors.forename: J
authors.initials: J
authors.lastname: Wardle
authors.forename: M J
authors.initials: MJ
authors.lastname: Jarvis
authors.forename: N
authors.initials: N
authors.lastname: Steggles
authors.forename: M
authors.initials: M
authors.lastname: Cartwright
mesh_terms: D000293:Adolescent; D002648:Child; D015331:Cohort Studies; D004041:Dietary Fats / Q000008:administration & dosage; D015444:Exercise / Q000523:psychology*; D005247:Feeding Behavior / Q000145:classification / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D006306:Health Surveys; D006801:Humans; D016013:Likelihood Functions; D008131:London; D008297:Male; D011627:Puberty / Q000523:psychology*; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology / Q000523:psychology*; D013315:Stress, Psychological / Q000150:complications*; D014505:Urban Population / Q000706:statistics & numerical data
chemical_list: D004041:Dietary Fats