Objective: The present study aimed to evaluate the prevalence of meeting health recommendations on diet and physical activity (having breakfast, eating fruit and vegetables, consumption of milk/yoghurt, performing moderate-to-vigorous physical activity, limiting television watching) and to assess junk snack food consumption in adolescents from southern Italy. The association between healthy behaviours and abdominal adiposity was also examined. Design: In a cross-sectional protocol, anthropometric data were measured by trained operators while other data were collected through a structured interview. Setting: Three high schools in Naples, Italy. Subjects: A sample of 478 students, aged 14–17 years, was studied. Results: The proportion of adolescents who met each of the health recommendations varied: 55?4% had breakfast on $6 d/week; 2?9% ate $5 servings of fruit and vegetables/d; 1?9% had $3 servings of milk/yoghurt daily; 13?6% performed moderate-to-vigorous physical activity for $60 min/d; and 46?3% watched television for ,2 h/d. More than 65% of adolescents consumed $1 serving of junk snack foods/d. Only 5% fulfilled at least three recommendations. Healthy habits tended to correlate with each other. As the number of health recommendations met decreased, the percentage of adolescents with high abdominal adiposity (waist-to-height ratio $0?5) increased. The trend was not significant when the proportion of overweight/obese adolescents was considered. Logistic regression analysis indicated that male gender and watching television for $2 h/d were independently associated with a higher waist-to-height ratio. Conclusions: Most adolescents failed to meet the five health recommendations considered. Male gender and excessive television watching were associated with abdominal adiposity.