Supplementing mineral tablets with selenium is not
beneficial in most cases, a new study from University of Nebraska-Lincoln and
Dolph Hatfield of the National Institutes of Health has revealed.
This trace element is essential in the diet of humans and
its deficiency may lead to various human disorders, including Keshan disease, a
heart disorderaffecting primarily children in certain provinces of China, where
the soil is deficient in selenium.
Alexey Lobanov and Vadim Gladyshev have revealed that evolutionary changes have
reduced the need for selenium, which occurs in proteins and is transported in
"Several trace elements are essential micronutrients
for humans and animals but why some organisms use certain ones to a greater
extent than others is not understood" said Gladyshev.
"We've found that
the evolutionary change from fish to mammals was accompanied by a reduced use
of proteins containing selenium," he added.
The evolved reduced need
of selenium invites questions regarding the widely accepted use of supplements
incorporating this trace element to maximize amounts of proteins that rely on
Supplements are taken
without knowing which groups of the population canbenefit.
According to the
researchers, only 20 pct of lower organisms use selenium-based proteins.
reduced utilization of selenium-containing proteins in mammals raises important
questions in human and animal nutrition, " he said.
expression is regulated such that people don't need to rely so heavily on
dietary selenium which is often present in excess amounts in the diet.
Individuals should consider their age, sex and medical needs before taking such
supplements on a regular basis," he added.
The study appears in open access journal Genome Biology.