Serum Selenium concentrations in pregnant women, in women with thyroid disorders and in healthy women in Hungary: Is there a need to supplement?

Introduction: Selenium is an essential trace element. Its recommended daily allowance is 55µg for women and 70µg for men, while in pregnancy the National Research Council recommends a dietary intake of 60µg. Selenium supplementation was reported to prevent colorectal cancer in the United States. Recently, the importance of an optimal selenium intake in thyroid diseases has been stressed by European guidelines. In the 1990s it was established that Hungary is a country with a marginal selenium deficiency. However, there have been few data reporting serum selenium concentrations in Hungary in the last decade.

Materials and methods: Serum selenium concentrations were determined in 33 healthy female study participants, 18 women with thyroid disorders and 97 pregnant women. Selenium concentrations were measured by hydride generation atomic absorption spectrometry following the nitric acid – perchloric acid – sulphuric acid digestion procedure.

Results: Serum selenium concentrations were significantly lower in pregnant women than in non-pregnant study particpants (46.77±12.04µg/l compared to 77.06±12.55µg/l). Selenium concentrations did not differ between healthy women and women with thyroid disorders. Selenium levels ranged from 22.95µg/l to 77.90µg/l in pregnant women with a median of 44.70µg/l. In non-pregnant women, selenium concentrations varied between 45.80µg/l and 107.43µg/l (median: 74.50µg/l).

Conclusions: Mean serum selenium concentrations of non-pregnant women determined in the last two years are higher than those reported in the early 1990s. This may be explained either by the use of a more advanced technique for selenium measurements and/or by a change in nutrition favouring the consumption of foodstuffs containing higher amounts of selenium. Serum selenium concentrations of pregnant women are low compared to international data and selenium supplementation may be considered in a few cases. Selenium supplementation of women with endocrine ophtalmopathy or autoimmun thyroiditis and concurrent high anti-TPO levels is currently recommended.