Holland & Barrett Selenium tablets are ideal for those looking to supplement with selenium when it is difficult to obtain through the diet. Selenium is an essential trace mineral, utilised by the body for various functions such as maintaining normal thyroid function, contributing to the normal functioning of the immune system, the maintenance of normal hair and nails and protecting cells from oxidative stress. It also supports body functions like helping with normal spermatogenesis and development of the sperm cells. Magnesium also contributes to normal function of the nervous system and normal energy yielding metabolism. Zinc also contributes to normal function of the immune system, cell division and contributes to normal fertility and reproduction.