Higher breakfast glycaemic load is associated with increased metabolic syndrome risk, including lower HDL-cholesterol concentrations and increased TAG concentrations, in adolescent girls

Almost all previous studies examining the associations between glycaemic load (GL) and metabolic syndrome risk have used a daily GL value. The daily value does not distinguish between peaks of GL intake over the day, which may be more closely associated with the risk of the metabolic syndrome. The aim of the present study was to investigate the cross-sectional associations between daily and mealtime measures of GL and metabolic syndrome risk, including metabolic syndrome components, in adolescents. Adolescents participating in the 14-year follow-up of the Western Australian Pregnancy Cohort (Raine) Study completed 3 d food records and metabolic assessments. Breakfast GL, lunch GL, dinner GL and a score representing meal GL peaks over the day were determined in 516 adolescents. Logistic regression models were used to investigate whether GL variables were independent predictors of the metabolic syndrome in this population-based cohort (3.5% prevalence of the metabolic syndrome). Breakfast GL was found to be predictive of the metabolic syndrome in girls (OR 1.15, 95% CI 1.04, 1.27; P<0.01), but not in boys. Other meal GL values and daily GL were found to be not significant predictors of the metabolic syndrome. When breakfast GL was examined in relation to each of the components of the metabolic syndrome in girls, it was found to be negatively associated with fasting HDL-cholesterol concentrations (P=0.037; beta=-0.004; 95% CI -0.008, -0.002) and positively associated with fasting TAG concentrations (P=0.008; exp(beta) = 1.002; 95% CI 1.001, 1.004). The results of the present study suggest that there may be an association between breakfast composition and metabolic syndrome components in adolescent girls. These findings support further investigation into including lower-GL foods as part of a healthy breakfast in adolescence, particularly for girls.