Variability of plasma/serum and erythrocyte selenium in the first year of life: a systematic review

Abstract

Selenium is particularly necessary in infants because of their rapid physical growth period in addition to being indispensable for neurodevelopment. Severe deficiency can lead to cardiomyopathy, hypothyroidism and faltering growth. However, selenium can be toxic at high doses. In the pediatric age group, plasma/serum and erythrocyte selenium levels seem to increase with age, except in the first year of life. Understanding the variability in selenium status during this period can help to identify infants at risk of deficiency and develop strategies for controlling and preventing its consequences. This review aimed to identify the extent and characteristics of the variability of selenium status during the first year of life. A search was conducted across five databases to find articles published until July 30, 2024, with no limitations on the language or date of publication. Articles were screened, data were extracted independently by two reviewers, and any disagreement was resolved by a third reviewer. A total of 22 studies comprising 1288 participants were included in this review, 21 of which assessed plasma/serum selenium and 12 assessed erythrocyte selenium. In the first four months of age, serum/plasma selenium decreased, remained stable, or increased depending on feeding, with an increase in supplemented formula-fed infants and breastfed infants of supplemented mothers. Erythrocyte selenium levels showed a declining trend, except in infants fed supplemented formula or breastfed by supplemented mothers. Variability of serum/plasma and erythrocyte selenium levels in the first year was associated with maternal selenium intake/supplementation and the selenium content of the infant’s diet.