A total of 1,671 school children aged 11, 13 and 15 years answered a questionnaire on diet, other health behaviour, social background, social network, health and life satisfaction. The proportions who ate fruit, vegetables, and rye bread every day were 77%, 64% and 94%. Moreover, 78% had fibre-containing breakfast every day and 79% had a regular lunch meal every day. 26% of the children received an optimal diet containing all of these five components every day, and 19% received less than three of these components every day. The proportions who consumed five unhealthy diet components every day (candy, chips, French fries, sausages/hamburgers, and sweet longdrinks) were 32%, 12%, 5%, 5%, and 18%. 39% received at least one of these unhealthy diet components every day. There was no association between intake of healthy and intake of unhealthy diet components. We found no age differences among boys regarding the healthy diet components but an increasing consumption of unhealthy components with increasing age. Among girls we found a decreasing consumption of both healthy and unhealthy components with increasing age. Healthy diet was associated with high social class, good health, positive life satisfaction, positive school assimmilation, and positive health behaviour.