TABLE 2.
Major clinical research and epidemiological studies conducted to date.
| SI No | Population | Number of subjects | Cancer research | Conclusion of the study | References |
|---|---|---|---|---|---|
| 1 | Malaysia | 62 (cases and control each) | Breast cancer | Breast cancer is associated with low serum selenium levels | Rejali et al. (2007) |
| 2 | Poland | 95 lung cancer, 113 laryngeal cancer, and corresponding controls | Lung and laryngeal cancers | Selenium level below 60 μg/L is associated with lung and laryngeal cancer | Jaworska et al. (2013) |
| 3 | Baltimore longitudinal study | 52 (cases) and 96 (controls) | Prostate cancer | The risk of prostate cancer is high in low plasma selenium cases | Brooks et al. (2001) |
| 4 | The university of California, san francisco, California | 568 with non-metastatic prostate cancer | Prostate cancer | Genetic variation in selenoproteins may be associated with high-grade disease and recurrence of prostate cancer | Gerstenberger et al. (2015) |
| 5 | Netherland | 64 esophageal squamous cell carcinoma, 112 esophageal adenocarcinomas, and 114 gastric cardia adenocarcinoma cases | Esophageal and gastric cancer | There is an inverse association between toenail selenium and risk of esophageal squamous cell carcinoma, esophageal adenocarcinoma, and gastric cardia adenocarcinoma | Steevens et al. (2010) |
| 6 | University of North Carolina hospital, North Carolina | 133 cases | Colorectal adenoma | The prevalence of colorectal adenoma is less with high selenium levels | Connelly Frost et al. (2006) |
| 7 | Swedish | 3,146 cases | Breast cancer | The survival rate is higher among the subjects who take selenium before the diagnosis of breast cancer | Harris et al. (2012) |
| 8 | Eastern United States of America | 1,312 cases | Prostate cancer | Selenium reduces prostate cancer incidence | Duffield-Lillico et al. (2003) |
| 9 | Szczecin, Poland | 546 cases | Breast cancer | Selenium level greater than 64.4 µg//L may be beneficial for breast cancer outcome | Lubinski et al. (2018) |
| 10 | Poland | 97 (cases) | Women with any cancer | The serum level of selenium level should be maintained between 70 and 90 μg/L for protection against cancer | Narod et al. (2019) |
| 184 (control) |