Article Text
Statistics from Altmetric.com
Introductory remarks
In part 35, we continue with S, and turn our attention to selenium, serine and sibutramine. Selenium is a trace element that is essential for health, whereas serine is a non-essential amino acid. However, to date, neither has been shown to be a necessary nutritional supplement for athletes to consume in addition to habitual dietary intake sources, as deficiency of both is unlikely to occur. By contrast, sibutramine is a weight-loss agent which was banned as a stimulant several years ago.
Selenium
N Lewis
Selenium (Se) is a trace element essential for human health, and deficiency is rare. Its essentiality is achieved through the functioning of 25 known selenoproteins in the form of selenocysteine, with enzymatic activities being assigned to 12 of the 25 proteins.1 Selenium is most well known as an antioxidant through its incorporation of glutathione peroxidase (GPx) of which there are several forms. Se deficiency gives rise to cardiomyopathy, skeletal muscle myopathy, osteoarthropathy, reduced immune function, certain cancers and viral disease.2 Skeletal muscle constitutes the main body pool of Se, comprising 50% of total body Se.3 The assessment of whole blood Se, plasma Se and red blood cell Se provides a less invasive method for the assessment of skeletal muscle Se content.3
The Se content of soil varies considerably depending on geographical locations.2 Se is found in various foods: meat and offal, seafood, cereals, nuts; with milk, dairy, fruit and vegetables being particularly low.
Selenium toxicity occurs at intakes >900 ug/d; Se deficiency …
Footnotes
-
Competing interests None.
-
Provenance and peer review Commissioned; not externally peer reviewed.