Aims: To determine the extent to which adiposity, as measured by the body mass index (BMI), tracks from adolescence to adulthood and whether this is a reflection of the tracking of food and nutrient intake. Methods: Height (m), weight (kg), BMI (kg/m2), food (% total food weight) and nutrient intake (g/d or mg/d) was measured in 202 men and women at 11-12 and 32-33 years. Tracking was assessed using Pearson Correlation analysis. Results: Significant tracking was observed for BMI (r=0.53, p<0.01) and, in addition, 96% of those in the highest quartile of BMI at 11-12 years had become overweight or obese by 32-33 years. Of the 5 food groups from the Balance of Good Health plate model 1,3 tracked significantly: fruit and vegetables (r=0.25, p<0.01), bread, other cereals and potatoes (r=0.24, p<0.01) and meat, fish and alternatives (r=0.17, p<0.05). Nutrient intake also tracked significantly, for example, with correlation coefficients of 0.16 (p<0.05) for fat, 0.25 (p<0.01) for total sugar and 0.29 (p<0.01) for vitamin C. Conclusions: Relative BMI as an index of adiposity does track from adolescence to adulthood and this is reflected, in part, by significant tracking of food and nutrient intake.