Selenium reduces prostate cancer

Selenium is known as the anti cancer mineral and is an essential trace element involved in several key metabolic activities via enzymes that are essential to protect against free radical (oxidative) damage and to regulate the immune system. Selenium is an essential part of glutathione peroxidase, an enzyme found to remove one of the major free radicals, hydrogen peroxide.

A number of very large studies on selenium supplementation, such as those in China and Finland have found significant reductions in cancer rates. In support of this a study just last week found that supplementation with 200 micrograms of selenium glycinate for 6 weeks increase the activities of blood enzymes such as glutathione, and reduces the levels of PSA, prostate-specific antigen, a marker for prostate cancer. It was only a small study of 30 middle-aged US men but the authors of the study said “If selenium could lower PSA [prostate-specific antigen] in healthy, middle-aged men, then it could be proposed that selenium can lower prostate cancer risk in some men, especially as part of an overall dietary plan,” (Zhang et al 2011).

Other studies have shown that high levels of selenium in the body have been linked with lower levels of lung, prostate and colorectal cancers. Selenium is thought to reduce the risk of developing cancers in two ways. Firstly, as selenium is an anti¬oxidant it helps protect the body from dangerous free radicals. Secondly, selenium has been known to prevent or slow down tumour growth. It does this in such a way that selenium enhances immune cell activity and suppresses the development of the blood vessel leading to the tumour resulting in reduced or no cancer growth. Studies have also shown that people with low levels of selenium have a greater incident of heart disease.

Good sources of selenium in the diet are whole grains, asparagus, garlic, eggs, mushrooms, lean meats and seafood's but the best known source is brazil nuts.

Zhang. W, E. Joseph, C. Hitchcock, R.A. DiSilvestro. 2011. Selenium glycinate supplementation increases blood glutathione peroxidase activities and decreases prostate-specific antigen readings in middle-aged US men. Nutrition Research, doi: 10.1016/j.nutres.2010.10.012