Background: Dairy intake may have beneficial effects with respect to becoming overweight, insulin resistance and metabolic syndrome (MS), although most of the available studies are cross-sectional and conducted among adults. The present study aimed to investigate whether dairy intake during adolescence and young adulthood protects against becoming overweight and (components of) MS at age 36years. Methods: Dairy intake was repeatedly measured between the ages of 13 and 36years among participants (n=374) of a Dutch prospective longitudinal cohort study. Being overweight and components of MS were examined at age 36years. A statistical method for longitudinal data, generalised estimating equations, was used to assess whether the time course of total dairy intake, high-fat and low-fat dairy was associated with being overweight and with (components of) MS. Results: The time course from age 13-36years for total dairy intake did not differ between overweight and non-overweight participants, nor for participants with and without MS at age 36years. Significant differences between groups were only observed at certain time points, mainly around the age of 21 and 27years. High-fat dairy intake during adolescence tended to be higher in subjects with lower weight, a lower body fat percentage, lower waist circumference and lower triglyceride concentrations at age 36years. In those having at least two risk factors for MS and high glycosylated haemoglobin, differences in dairy intake were in the opposite direction. Conclusions: These results do not support the hypothesis that dairy consumption protects against potentially becoming overweight and metabolic disturbances. © 2011 The Authors. Journal compilation © 2011 The British Dietetic Association Ltd.