Background: Adolescence is an important developmental period in which dietary habits and cardio-metabolic risk factors may establish and track into adulthood. Adolescence may therefore be an opportunity for intervention. However, the importance of diet in the evolution of cardio-metabolic risk factors in young people is poorly understood.
Objectives: To examine changes in dietary patterns and cardio-metabolic risk factors between the ages of 14 and 17 years in 1,433 adolescents from the Western Australian Pregnancy Cohort (Raine) Study.
Methods: BMI, waist circumference, fasting serum lipids, glucose and insulin were measured at 14 and 17 years. Dietary intake was estimated using an evaluated FFQ at both ages and two major dietary patterns were identified using factor analysis: ‘Western’ (high in confectionery, processed foods) and ‘Healthy’ (high in fruit, vegetables, wholegrains). Mixed models assessed longitudinal changes in dietary pattern scores and cardio-metabolic risk factors between 14 and 17 years of age, adjusting for age, pubertal stage, physical fitness and misreporting of dietary intake.
Results: A 1 SD increase in ‘Western’ pattern score between 14 and 17 years was associated with a doubling of risk for overweight or obesity (p=0.004) and an average increase in waist circumference of 1.5cm (p<0.01) in boys and girls. In girls only, an 1 SD increase in ‘Western’ pattern score was associated with increases of 6 - 7 % in insulin, insulin resistance (HOMA) and triglycerides, independently of BMI (all p<0.01).
Conclusions: A ‘Western’ dietary pattern during adolescence is prospectively associated with increases in cardio-metabolic risk factors.