Effect of selenium on breast cancer in women – part I

Background
Breast cancer is the most common malignant tumour in women in Poland. To reduce the risk of breast cancer, appropriate prevention is necessary. Numerous studies conducted over many years in Poland and throughout the world have demonstrated a significant effect of selenium on prevention of disease, including breast cancer in women. The following paper aims to present the literature on effects of selenium (Se) on prevention of breast cancer in women.

Material and methods
Based on national and international literature, the paper presents information on the role of selenium (Se) in prevention of breast cancer in women.

Results
Numerous studies conducted in research centres in Poland and abroad have shown that female patients with breast cancer and individuals with gastrointestinal cancer have significantly lower selenium concentration in their blood serum and whole blood, as well as significantly lower GSH - Px activity in plasma and red blood cells, compared to healthy women. Low selenium concentration may indicate an increased risk of breast cancer. Selenium is an essential co-factor in the production of antioxidant enzymes and may affect the development of cancer. Clinical trials which assessed selenium content in food showed that its supplementation reduced cancer mortality.

Conclusions
Results of numerous national and prospective international studies indicate that low selenium intake and/or concentration in serum/plasma/nails is a high-risk marker of the majority of cancers, including breast cancer in women.