Introduction
Children in developed countries watch a lot of television.Surveys suggest that time spent watching television during childhood and adolescence might even exceed time spent in school.1 There is increasing concern that the amount of television watched by children could have adverse effects on health. Television viewing might not only displace more energetic activities (contributing to poor fitness and obesity), but also encourage poor dietary habits, violent behaviour, and substance abuse due . 2Studies in children and adolescents have linked television viewing to obesity,3–6 poor physical fitness,7,8 lipid abnormalities,9 and smoking.10 However, several studies have found the associations to be weak or non-significant,11–13 and none has addressed the long-term effects of childhood television viewing. In particular, there is no information on whether childhood television viewing affects adult health. To address this issue, we examined the association between child and adolescent television viewing and a range of adult health indicators in a birth cohort of approximately 1000 New Zealanders.