The relationship between vitamin C intake, general health practices, and mortality in Alameda County, California.

To evaluate the relation between vitamin C intake and mortality, a prospective follow-up study was carried out among 3,119 noninstitutionalized adult residents of Alameda County, California who had completed a detailed lifestyle questionnaire around the beginning of 1974. During 10 years of follow-up, 276 deaths have been identified. The questionnaire information and mortality data indicate that this sample is fairly representative of the county population and similar to the United States population. There is no important relation between the estimated 1974 vitamin C intake at levels above and below 250 mg per day and subsequent mortality from cancer, circulatory disease, all other causes, or all causes combined. However, there is an inverse relation between combinations of several health habits and total mortality. The health habits include never smoking cigarettes, regular physical activity, moderate or no use of alcohol, 7-8 hours of sleep per day, and maintaining proper weight. The conclusions with regard to vitamin C are limited by the crudeness with which the dietary intake has been estimated and changes in intake over time. Nevertheless, these results are not consistent with any substantial relation between vitamin C intake and subsequent mortality.