Sodium in the Finnish diet: II. Trends in dietary sodium intake and comparison between intake and 24-h excretion of sodium

Objective: To estimate cross-sectional and long-term dietary sodium intakes and sources in Finland, and to evaluate the validity of 48-h recall to assess sodium intake. Design: Cross-sectional dietary surveys and food availability data (Food Balance Sheets). Setting: Dietary surveys were carried out in Finland in 1992, 1997 and 2002. Food availability data were collected from 1980 to 1999. Subjects: A stratified random sample was drawn from the population register. The total number of participants in the three dietary surveys was 6730. In the subsample for urine collection, the number of participants was 879. Interventions: Nutrient intakes were estimated on the basis of a 3-day food diary in 1992, a 24-h recall in 1997 and a 48-h recall in 2002. The 24-h urinary excretion of sodium was used to validate sodium intake. In addition, salt intake was estimated based on Food Balance Sheets. Results: Sodium intake has slowly decreased since the early 1980s. Reported daily sodium intake correlated significantly with sodium excretion. Conclusions: Sodium intake has decreased during the last two decades, but is still higher than the recommended daily intake. Sodium intake estimation based on dietary surveys and food availability data is a valid method provided that the food composition database is up to date and of good quality. Sponsorship: All surveys were funded by the National Public Health Institute in Finland and the Ministry of Social Affairs and Health.