Selenium: Geochemical distribution and associations with human heart and cancer death rates and longevity in China and the United States

Abstract

The geochemistry of available soil Se varies enormously in different localities, and the corresponding amounts moving up through crops to food vary accordingly. In a belt extending from northeastern to south central China, the available soil Se was measured by human blood Se levels. Severe deficiency occurred at 8-26 ng/mL; subadequate amounts occurred in large areas with 32-83 ng/mL; adequate amounts of 200-300 ng/mL occurred in large cities; and toxic amounts of 3000-7800 ng/mL occurred in terrace areas where runoff from the uplands evaporated, and in certain other soils. Some heart deaths (Keshan Disease) occurred in children 1 to 10 yr of age in the most deficient areas, but were prevented by 230-900 micrograms/wk Se supplementation. One mg Se/wk was the adult dosage. In Se deficient areas, the life span of adults was lowered severely (35 to 45 yr), with heart muscle damage common at autopsy. Se and Zn deficiencies are apparently associated with stomach cancer. The geochemistry of Se in the USA is also highly variable, blood Se ranging from 100-350 ng/mL. Se data for individuals are limited; however, ischemic heart death correlated inversely with blood Se in 25 cities of 22 states (r = -.70; p less than .01). Counties of Wisconsin and Florida are highly variable in human heart death and cancer death rates, as are the 50 states, suggesting Se geographic variability.

Malnutrition and Infection: An Update

“…Keshan disease was a progressive and fatal pulmonary disease in East Asia, which was found to be associated with low selenium status in the population 66 . Beck et al 67 looked at murine models of pulmonary infections using a usually benign mouse coxsackie virus which produced a self-limited, mild respiratory infection in well-nourished mice.…”

Anti-oxidant ebselen delays microvascular thrombus formation in the rat cremaster muscle by inhibiting platelet P-selectin expression

“…Despite the advances in medical science, thrombosis is still an exceptionally clinically relevant problem. In the past, a relationship between low serum selenium concentrations and increased risk of death from acute coronary heart disease and from myo-cardial infarction has been suggested (1)(2)(3). In addition, low platelet glutathione peroxidase activity is frequently observed in those cohorts of patients (4,5).…”

Chemoprevention of prostate cancer with selenium: An update on current clinical trials and preclinical findings

“…Several challenges have been encountered in the study of Se as a chemopreventive agent. Accurate assessment of dietary intake of Se is difficult due to the variability of the Se content in foods due to growth conditions, crops, and local soil [Jackson, 1988]. Furthermore, regardless of Se intake, measurement of Se in target tissue is a challenge.…”