Selenium Supplementation may Benefit Ovarian Cancer Risk in African American Women

by | Aug 28, 2017 | 2017, Cancer, Minerals, Selenium, Women's Health

Written by Greg Arnold, DC, CSCS. African American study participants who supplemented with 20 micrograms of selenium had a 30% lower risk of developing ovarian cancer compared to those who supplemented with no selenium.

seleniumApproximately 22,440 women in the United States will be diagnosed with ovarian cancer in 2017 and with number of deaths estimated at 14,080. Approximately 1.3 percent of women will be diagnosed with ovarian cancer at some point during their lifetime, based on 2012-2014 data. In 2014, there were an estimated 222,060 women living with ovarian cancer in the United States.1

Since ovarian cancer has very few symptoms, diagnosis is usually not made until the cancer has become advanced. This has led to a primary focus on prevention 2. The use of antioxidants during cancer therapy is currently a topic of heated debate because of an overall lack of clear research findings. Some studies suggest that antioxidants can ameliorate the toxic side effects of therapy without affecting treatment results, while other data suggest that antioxidants can interfere with radiotherapy or chemotherapy. Current knowledge is insufficient and precludes generalizations or specific recommendations concerning antioxidant use for those at high risk of cancer or for cancer treatment 3. Therefore, finding evidence of the effectiveness of antioxidant therapy in cancer treatment is warranted.

With that objective in mind and since no previous study has evaluated any potential associations of antioxidant intake with the risk of ovarian cancer in African-American women who have high mortality from the disease, researchers 4 compared 386 African American women with ovarian cancer to 622 age-matched controls in a large population-based multicenter case controlled study of women enrolled in the African American Cancer Epidemiology Study 5.

Dietary information was assessed from a self-administered food frequency questionnaire that included questions on 110 foods and beverages that were consumed over the previous year. 6

  • The researchers found that women who supplemented with more than 20 micrograms/day of selenium had an approximately 30% lower risk of ovarian cancer compared to those with no supplemental intake (p-trend = 0.035).
  • This inverse association was stronger in current smokers and produced an 87% reduced ovarian cancer risk compared to those who did not supplement with selenium (p-trend = 0.001).
  • There was no association with dietary selenium (p = 0.1)
  • Although an increasing inverse trend was seen with increased intake of total carotenoids, statistical significance was not reached (P = 0.07–0.60).
  • There was no association with dietary or supplemental intake of vitamin C (p = 0.7) or vitamin E (p = 0.8). 

The strength of this study is the large sample (386) recruitment of African –American women with ovarian cancer. The large population-based controls (622) from various geographical regions and diverse socioeconomic status and lifestyles also strengthened the study results. Limiting factors include the dietary recall and selection bias that occurs in case-control studies. Also if blood work had been done to determine levels of the circulating antioxidants that were studied, more accurate results might have been obtained. Finally, selenium concentrations in soil vary greatly by location; therefore, nutrient composition databases may inconsistently reflect the actual intake of selenium from food.

Researchers conclude, “our data suggest that higher intake of supplemental selenium may be inversely associated with risk of ovarian cancer in African-American women” but that “additional studies are needed to assess dietary associations with ovarian cancer in African-American women, specifically those that include antioxidants and other nutrients that may be lacking in this population.”

Source: Terry, Paul D., Bo Qin, Fabian Camacho, Patricia G. Moorman, Anthony J. Alborg, Jill S. Barnholtz-Sloan, Melissa Bondy et al. “Supplemental Selenium May Decrease Ovarian Cancer Risk in African-American Women.” The Journal of Nutrition 147, no. 4 (2017): 621-627.

© 2017 American Society for Nutrition

Posted August 28, 2017.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com.

References:

  1. Institute NC. Ovarian Cancer. 2017; Overview of ovarian, fallopian tube, and primary peritoneal cancer. Available at: https://www.cancer.gov/types/ovarian. Accessed August 22, 2017, 2017.
  2. Seifried HE, McDonald SS, Anderson DE, Greenwald P, Milner JA. The antioxidant conundrum in cancer. Cancer research. 2003;63(15):4295-4298.
  3. Schildkraut JM, Alberg AJ, Bandera EV, et al. A multi-center population-based case–control study of ovarian cancer in African-American women: the African American Cancer Epidemiology Study (AACES). BMC cancer. 2014;14(1):688.
  4. Terry PD, Qin B, Camacho F, et al. Supplemental Selenium May Decrease Ovarian Cancer Risk in African-American Women. The Journal of Nutrition. 2017;147(4):621-627.
  5. Boucher B, Cotterchio M, Kreiger N, Nadalin V, Block T, Block G. Validity and reliability of the Block98 food-frequency questionnaire in a sample of Canadian women. Public health nutrition. 2006;9(1):84-93.
  6. Hatfield DL, Yoo M-H, Carlson BA, Gladyshev VN. Selenoproteins that function in cancer prevention and promotion. Biochimica et Biophysica Acta (BBA)-General Subjects. 2009;1790(11):1541-1545.