[Selenium in serum and plasma: epidemiology and reference values].

Area of Science:

• Environmental Health
• Clinical Chemistry
• Nutritional Science

Context:

• Selenium (Se) is an essential trace element crucial for human health.
• Serum and plasma selenium levels are important biomarkers for assessing nutritional status and potential health risks.
• Geographical variations in selenium intake and status are well-documented globally.

Purpose:

• To systematically review and analyze existing literature on selenium levels in human serum and plasma.
• To identify and describe variations in selenium levels across different populations and geographical regions.
• To establish reference values for selenium in European and Latin American countries and provide a framework for future research.

Summary:

• A comprehensive literature review analyzed 161 European studies (1972-2009) involving 49,869 healthy adults, revealing serum/plasma Se levels ranging from 48.2 to 124.00 µg/L, with a weighted average of 85.19±14.58 µg/L.
• Significant differences in selenium levels were observed across European countries, regions, measurement techniques, sex, and age groups. For European children (<19 years), the weighted average was 74.21±9.50 µg/L.
• Limited data from 11 Latin American studies indicated higher serum/plasma Se levels in adults (91.51±18.78 µg/L) and children (<15 years, 93.25±39.20 µg/L) compared to Europeans, with newborns showing the highest levels (130±30 µg/L).

Impact:

• Findings highlight significant geographical and demographic variations in selenium status, underscoring the need for region-specific reference values.
• The study identifies measurement techniques as a significant factor influencing reported selenium levels, emphasizing the importance of standardization.
• Results indicate a critical need for well-designed population studies in Latin America to establish reliable regional reference values for serum and plasma selenium.