Objective: To determine the diet quality of a group of young adults and explore its associations with two food-related behaviours (involvement in meal preparation and consumption of commercially prepared meals).

Design: Cross-sectional study of young adults. Sample characteristics, food-related behaviours and dietary intake were assessed using a self-administered questionnaire including an FFQ. Diet quality was measured using the fifteen-item Dietary Guideline Index (DGI) designed to assess adherence to Australian dietary guidelines. One-way ANOVA, t tests and multiple linear regression analyses were used to explore the relationships between DGI scores, sample characteristics and food-related behaviours.

Setting: University students enrolled in an undergraduate nutrition class, Melbourne, Australia.

Subjects: Students (n 309) aged 18-36 years.

Results: The DGI score was normally distributed, with a mean score of 93·4 (sd 17·1) points (range 51·9-127·4 points), out of a possible score of 150 points. In multivariate analyses adjusted for age, sex, nationality, BMI and maternal education, cooking meals for oneself was positively associated with DGI score (β = 0·15; 95 % CI 1·15, 10·03; P = 0·01); frequency of takeaway and frequency of convenience meal consumption were inversely associated with DGI score (β = -0·21; 95 % CI -9·96, -2·32; P = 0·002 and β = -0·16; 95 % CI -7·40, -0·97; P < 0·01, respectively).

Conclusions: Cooking meals for oneself was linked to higher diet quality among young adults, while consumption of commercially prepared meals was associated with poorer diet quality. Maintaining education programmes that promote cooking skills within young adults has the potential to improve DGI scores.