Breast cancer is the most common cancer in women.
More than 178,000 new cases of breast cancer were diagnosed in 2007, and more than 40,000 women died from it that year.
Obviously, any lifestyle factor that might help is of great interest to all women and their families.
Vitamin D and omega-3 fatty acids from seafood have shown particular promise ... see our sidebar, “Fishy nutrients vs. breast cancer”.
Three years ago, a novel study looked for links between women's use of vitamin and calcium supplements, and their risk for breast cancer risk.
The researchers reached an encouraging conclusion: “Vitamins and calcium intake are protective for breast cancer.” (Vergne y et al. 2010).
Fishy nutrients vs. breast cancer
Many lab and epidemiological studies suggest that vitamin D3 and omega-3s – which abound only in seafood and supplements – may help deter or control various kinds of breast cancer.
You'll find these reports and more in the Omega-3s & Immunity  and Vitamin D & Immunity sections of our news archive:
Women who took vitamin supplements were 30 percent less likely to have breast cancer, and women who took calcium supplements were 40 percent less likely to have breast cancer (see “Breast & Brain Health Boosted by Vitamins”).
Few other studies have compared women's supplement habits to their risk for breast cancer have produced mixed but mostly positive indications:
  • “Multivitamin use along with practice of other health-promoting behaviors may be beneficial in improving breast cancer outcomes in select groups of survivors.” (Li K et al. 2011)
  • “Multivitamin use along with practice of other health-promoting behaviors may be beneficial in improving breast cancer outcomes in select groups of survivors. (Kwan ML et al. 2011)
  • “… multivitamin use has little or no influence on the risk of common cancers, CVD, or total mortality in postmenopausal women.” (Neuhouser ML et al. 2009)
Now, findings from a study in more than 7,000 postmenopausal women suggest that multivitamin/mineral supplements may increase the survival chances of women who develop invasive breast cancer.
The term “invasive breast cancer” refers to tumors that spread from milk glands or ducts into the breast tissue … such as invasive ductal carcinoma or infiltrating lobular carcinoma.
U.S. study links multivitamin/mineral supplements reduced risk for invasive breast cancer
The study was conducted by researchers at Albert Einstein College of Medicine (AECM), with assistance from 10 other prominent universities, hospitals, and cancer research institutes.
It was conducted as part of the Women's Health Initiative (WHI) Clinical Trials and the Women's Health Initiative (WHI) Observational Study, which collected relevant information from 161,608 postmenopausal women ages 50 to 79 enrolled at 40 U.S. clinical centers from 1993-1998.
The new analysis of WHI data – led by Professor Sylvia Wassertheil-Smoller, Ph.D., of AECM – focused on 7,728 participants who were diagnosed with invasive breast cancer during the WHI study period and were followed for an average of seven years after their diagnosis.
After enrolling in the WHI and during repeated follow-up visits, all participants provided extensive information about their health … including whether they'd taken a multivitamin/mineral supplement at least once a week during the prior two weeks.
About 38 percent of the 7,728 women who developed invasive breast cancer during the WHI were using the supplements. The vast majority were taking such supplements before their breast-cancer diagnosis.
A comparison of death rates revealed that women with invasive breast cancer who took multivitamin/mineral supplements were 30 percent less likely to die from their cancers than women who hadn't taken such supplements.
As Dr. Wassertheil-Smoller said, “Our study offers tentative but intriguing evidence that multivitamin/mineral supplements may help older women who develop invasive breast cancer survive their disease.” (AECM 2013)
Multivitamin/mineral supplements are the most commonly consumed dietary supplements in the U.S., usually contain 20-30 vitamins and minerals … usually at levels at or below U.S. Recommended Dietary Allowances (RDAs).
Could differences between the vitamin users and non-users account for the findings?
The researchers looked at many possible “confounding” factors, including any additional supplements taken, smoking, education, race/ethnicity, weight, depression, alcohol use, physical activity, age at breast cancer diagnosis, and diabetes.
And the link between regular use of multivitamin/mineral supplements and reduced risk of death persisted after these factors were taken into account.
Controlling for these other factors strengthens our confidence that the association we observed – between taking multivitamin/mineral supplements and lowering breast-cancer mortality risk among postmenopausal women with invasive breast cancer – is a real one,” said Dr. Wassertheil-Smoller.
But as she noted, “… further studies are needed to confirm whether there truly is a cause-and-effect relationship here. And our findings certainly cannot be generalized to premenopausal women diagnosed with invasive cancer or to other populations of women.” (AECM 2013)
The WHI is sponsored by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.
Albert Einstein College of Medicine (AECM) Multivitamins May Protect Older Women With Invasive Breast Cancer. October 9, 2013. Accessed at Kwan ML, Greenlee H, Lee VS, Castillo A, Gunderson EP, Habel LA, Kushi LH, Sweeney C, Tam EK, Caan BJ. Multivitamin use and breast cancer outcomes in women with early-stage breast cancer: the Life After Cancer Epidemiology study. Breast Cancer Res Treat. 2011 Nov;130(1):195-205. doi: 10.1007/s10549-011-1557-4. Epub 2011 May 11. Li K, Kaaks R, Linseisen J, Rohrmann S. Vitamin/mineral supplementation and cancer, cardiovascular, and all-cause mortality in a German prospective cohort (EPIC-Heidelberg). Eur J Nutr. 2012 Jun;51(4):407-13. doi: 10.1007/s00394-011-0224-1. Epub 2011 Jul 22. Neuhouser ML, Wassertheil-Smoller S, Thomson C, Aragaki A, Anderson GL, Manson JE, Patterson RE, Rohan TE, van Horn L, Shikany JM, Thomas A, LaCroix A, Prentice RL. Multivitamin use and risk of cancer and cardiovascular disease in the Women's Health Initiative cohorts. Arch Intern Med. 2009 Feb 9;169(3):294-304. doi: 10.1001/archinternmed.2008.540. Wassertheil-Smoller S, McGinn AP, Budrys N, Chlebowski R, Ho GY, Johnson KC, Lane DS, Li W, Neuhouser ML, Saquib J, Shikany JM, Song Y, Thomson C. Multivitamin and mineral use and breast cancer mortality in older women with invasive breast cancer in the women's health initiative. Breast Cancer Res Treat. 2013 Oct;141(3):495-505. doi: 10.1007/s10549-013-2712-x. Epub 2013 Oct 9.