Cancer mortality correlation studies--III: statistical associations with dietary selenium intakes

Area of Science:

• Nutritional Epidemiology
• Oncology
• Environmental Health

Background:

• Cancer remains a leading cause of mortality worldwide.
• Dietary factors are increasingly recognized for their role in cancer prevention.
• Selenium is an essential trace element with known antioxidant properties.

Purpose of the Study:

• To investigate the association between dietary selenium intake and age-corrected cancer mortality rates across 27 countries.
• To explore the relationship between blood selenium levels and cancer mortality.
• To evaluate the potential cancer-protective effects of selenium in humans.

Main Methods:

• Correlation analysis between dietary selenium intake (estimated from food consumption data) and age-corrected cancer mortalities for 17 major body sites in 27 countries.
• Comparison of cancer mortalities with selenium concentrations in whole blood samples from healthy donors.
• Review of existing animal studies on selenium and tumor development.

Main Results:

• Significant inverse correlations were observed between dietary selenium intake and mortality from cancers of the large intestine, rectum, prostate, breast, ovary, lung, and leukemia.
• Weak inverse associations were noted for pancreatic, skin, and bladder cancers.
• Similar inverse correlations were found between cancer mortalities and blood selenium concentrations.

Conclusions:

• The findings support the hypothesis that selenium possesses cancer-protective effects in humans.
• Increasing dietary selenium intake is proposed as a strategy to lower human cancer risk.
• A significant decline in cancer mortality in Western nations could be achieved by doubling current dietary selenium intake.