Iron status in a multiethnic population (age 36-80 yr) in northern Norway: the SAMINOR study

Objectives: Northern Norway consists of a multiethnic population of Sami and non-Sami. We evaluated iron status in these two groups with respect to gender, age and residence. Methods: In 2002-2004, a cross-sectional study of health and living conditions in areas with both Sami and Norwegian populations, SAMINOR, was performed in northern Norway. In total, 16 538 men and women between the age of 36 and 79 yr, participated. Response rate was 60.9%. Information about ethnic belonging, s-ferritin and transferrin saturation were available in 14 873 persons (54.8% of the invited sample). A questionnaire delivered at attendance had several questions on family background language and self-perceived ethnicity. Results: Sami men and women living in the inland areas had significantly higher mean s-ferritin than non-Sami living in the same area (P < 0.0001). The inland Sami also had significantly higher s-ferritin than the coastal Sami and non-Sami populations, both genders (P < 0.013). S-ferritin increased with increasing age for all women, while the opposite was true for men. Lifestyle factors had impact on s-ferritin level. Also mean transferrin saturation was higher at the inland residents but significant only for the male participants. Conclusion: The results from our analyses indicate that individuals living at the inland areas have higher s-ferritin and transferrin saturation than the coastal population. There were also differences in iron levels between Sami and non-Sami groups at the inland areas. Iron levels are influenced by lifestyle factors. The observed differences in iron levels might therefore be explained by nutritional habits.