Selenium: from health to the biological food chain

Selenium is an essential trace element which plays a role in the anti-oxidant activity in the cell. Selenium homeostasis needs to be strictly regulated as it can be harmful in excess or limiting amounts. Selenium has been studied extensively in its incorporation into seleneocysteine and subsequently seleneoproteins have been found in species ranging from algae to humans. Here within, a detailed review follows of selenium uptake within the human body and pathogenic implications. Also selenium toxicity will be examined in other organisms as well as its importance in biowebs and its role in the food chain. Lastly, the pathways of selenium in the cells will be discussed as well as future directions.