Although selenium has, up until now, been considered a healtlhy addition to the diet, due to the hgih levels of antioxidant which can help to protect skin from suffering from sun damage, it is now thought that if people already have selenium in their diet, they should steer clear of adding extra in the form of supplements. This is because having too much selenium can potentially lead to a poor immune system, cognitive decline and the onset of type 2 diabetse.
During the research, scientists studied the effects of high levels of selenium on members of the population. They found that, in men, it increased fertility and reduced their chances of getting bladder, lung and prostate cancer. They also discovered, however, that these benefits only were of value if the starting levels of selenium in the body were low.
Based on the research, sceintists now advise that only those who have a lselenium blood level of lower than 122 micrograms per litre of blood should take selenium supplements. Those who have upwards of this figure should steer clear of it due to the negative associations that have been found with this supplement.
A previous study has also indicated that high levels of selenium in the body are linked to a raise in cholesterol levels of around 10 per cent. This occurs when the body absorbs too much selenium, when it is added artificially to the diet.