Blood selenium levels and contribution of food groups to selenium intake in adolescent girls in Iceland

Abstract

Background/objectives: Significant changes have been reported in dietary habits and food availability in Iceland that would be expected to compromise selenium intake and status, especially among young people. These include substantial decreases in the consumption of fish and milk, as well as the selenium content of imported wheat. The aim of this study was to assess selenium in the diet and whole blood of adolescent girls, as well as define the most important foods contributing to intake and blood concentrations of selenium. Design: The subjects were 96 randomly selected girls, aged 16Á20, who answered a validated food frequency questionnaire (FFQ) for dietary assessment. Selenium intake from each food group was calculated in mg/day. Blood samples were collected for measurement of whole blood selenium. Results: Mean dietary selenium was 51925 mg/day. Milk/dairy products, including cheese, contributed 36914% of total dietary selenium; fish 18912%; and bread/cereal products 1396%. Mean whole blood selenium was 117912 mg/l (range 90Á208); nearly 90% of subjects were above the optimal level of 100 mg/l. Fish and bread/cereal products were the only foods significantly correlated with selenium in blood (r 00.32; P00.002 and r 00.22; P00.04, respectively) while no correlation was found with milk and dairy products in spite of their greater contribution to total selenium intake. Conclusion: In this population of Icelandic adolescent girls, selenium intake and status seem acceptable. Judging from associations between intake and blood levels, fish and cereals may be the most important contributors to blood selenium.