Reduction of Cancer Risk with an Oral Supplement of Selenium

Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA.
Biomedical and Environmental Sciences (Impact Factor: 1.65). 10/1997; 10(2-3):227-34.
Source: PubMed


The hypothesis that a dietary supplement of selenium (Se) may reduce cancer risk was tested experimentally in humans. Patients with histories of basal/squamous cell carcinomas of the skin were assigned randomly in double-blind fashion to daily oral supplements of either Se-enriched yeast (200 micrograms Se/day), or a low-Se yeast placebo. A total of 1312 patients recruited in 1983-1990 were followed with regular dermatologic examinations through 1993 for a total of 8269 person-years of observation. Skin cancer diagnoses were confirmed histologically. Plasma Se concentration was determined at 6-12 months intervals. All deaths and patient-reported illnesses were recorded; reported cancers were confirmed and documented by consultation with the patient medical care providers. The results indicate that Se did not significantly affect the primary endpoints: incidences of recurrent basal/squamous cell carcinomas of the skin. However, Se-treatment was associated with reductions in several secondary endpoints: total mortality, mortality from all cancers combined, as well as the incidence of all cancers combined, lung cancer, colorectal cancer and prostate cancer. The consistencies of these associations over time, between study clinics and for the leading cancer sites strongly suggests benefits of Se-supplementation for this cohort of patients, supporting the hypothesis that supplemental Se can reduce cancer risk. Although Se did not shown protective effects against non-melanoma skin cancers, the suggested reductions in risks to other frequent cancers demand further evaluation in well controlled clinical intervention trials.

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    • "Selenium may have an anti-carcinogenic effect. Observational studies indicate that death from cancer, including lung, colorectal, and prostrate cancers is lower among people with higher blood levels or intake of selenium (Combs et al., 1997). The role of selenium for the proper functioning of the thyroid gland has also been documented. "
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    ABSTRACT: The soil contents of trace elements selenium, chromium and manganese were measured to determine their impact on the plasma levels of 160 healthy adult Nigerians in five different experimental locations in Cross River and Akwa Ibom States, South -South Nigeria. The mean (±SD) soil selenium, chromium and manganese concentrations were 2.86 ± 3.97, 15.93 ± 3.35 and 90.33± 42.65 mg/kg, respectively. Manganese soil concentration was the highest and selenium soil concentration was the lowest in all the locations. The mean (±SD) plasma selenium, chromium and manganese concentrations were 0.006, 0.111 ± 0.031 and 0.028 ± 0.024 mg /1, respectively. There were no significant differences between the concentrations of the trace elements in the soil and the plasma levels as determined by t-test. Plasma levels of chromium and manganese according to the study were adequate but that of selenium was low.
    AFRICAN JOURNAL OF BIOTECHNOLOGY 08/2013; 12(Vol 12(34)):5339-5346. DOI:10.5897/AJB12.107 · 0.57 Impact Factor
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    • "some semiconductor manufacturers ). Plants can be used both as a natural source of the anticarcinogenic compound methylselenocysteine (Combs et al., 1997; Orser et al., 1999) and for cleaning up Se-contaminated areas (Srivastava et al., 2011). Although toxicity of Se to plants growing under natural conditions has not been reported, symptoms of toxicity to crop plants have been described. "
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    ABSTRACT: The present study was investigated to evaluate the uptake and accumulation of selenium (Se) by the stem cuttings of Portulaca oleracea L. grown in alfisol amended with various concentrations of Se. P. oleracea accumulated a maximum of 63.4 µg g(-1) dry weight in a short growth period of 42 days. The order of accumulation of Se among the plant parts was leaves (31.5 μg g(-1)) > stems (16.4 μg g(-1)) > roots (15.5 μg g(-1)). The accumulation potential was fourfold higher than the plant available concentration of 15.2 μg g(-1) of Se g(-1) of soil (diethylenetriaminepentaacetic acid extracted). Although the plant was able to accumulate Se in their tissues, increase in Se concentrations in soil caused a concentration-dependent decrease in the growth rate of plants (regeneration of leaves, number of leaves, number of roots, root length, stem length and biomass).
    Toxicology and Industrial Health 01/2013; 31(5). DOI:10.1177/0748233713475502 · 1.86 Impact Factor
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    • "The combination of selenium and vitamin E can offer additive effects on the destruction of enzymes important in the progression of prostate cancer [107]. While supplementation can reduce cancer risk [108], serum selenium levels higher than 150ng/mL may negatively affect patient's mortality rate [109]. (v) Mixed tocopherols: 400 IU twice a day. "
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    ABSTRACT: While prostate cancer is the most common male malignancy in the West, it is ranked as the number two cancer death for non-smokers in many developing countries. This case study demonstrates how an early stage prostate cancer might be treated by a comprehensive and evidence-based nutritional cum phytotherapy if patient is given the option of using it. According to the ANMP (, a nutritional therapy is used to treat, control, or prevent chronic disorders by impacting on the hormonal, neurological, and immune functions of the patient. It may take a decade or longer to develop a malignancy. Three quarter of prostate cancer occurs in men over fifty five years when they go through andropause, which is evidenced partly by elevation in their oestrogen levels. However, being overweight or obese may trigger early progression of prostate cancer in men.
    01/2012; DOI:10.6000/1927-3037/2012.01.03.06
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