The present study describes food habits in adolescents in thirty-five countries and regions (European countries/regions, Israel, Canada and the USA), based on the food-frequency questions from the cross-sectional Health Behaviour in School-aged Children survey of the year 2001-2. A total of 162,305 pupils of 11, 13 or 15 years of age completed an anonymous standardised questionnaire on health and lifestyle factors during one school hour. Large differences in food habits between countries were found: the consumption frequency of fruit varied from on average 2.8 to 5 d/week, the consumption of vegetables varied from on average 2.4 to 5.5 d/week, the consumption of soft drinks varied from 2.1 to 5 d/week and sweet consumption from 2.6 to 5 d/week. Methodological problems in comparing between countries are discussed. Nonetheless, the results indicate a need for national and international health promotion programmes to improve adolescents' food habits.