Written by Greg Arnold, DC, CSCS. Use of cod liver oil, milk, and salmon or tuna consumption significantly decreases risks of breast cancer.
Breast cancer is second only to lung cancer as the biggest cancer killer of American women, with an estimated 40,580 deaths in 2004 (1). It is estimated that breast cancer accounted for up to 25% of the $156.7 billion in cancer costs in the U.S. in 2001 (2).
Now a new study (3) has found that vitamin D, known to help back pain in women (4) and also shown to be lower in women with breast cancer (5), may help breast cell health. In the study, 972 women from the Ontario Breast Cancer Study (6) completed an interview about their sun exposure history and their dietary and supplemental vitamin D intake with respect to 3 age groups: 10–19, 20–29, and 45–54 years. Sun exposure information included the number of days per week on which at least half an hour was spent outside, total number of outdoor activity episodes of at least half an hour during the summer, or ever having a job involving at least half an hour of outdoor work per day.
Dietary intake of vitamin D included the number of glasses of milk per week (none, <5, 5–9, 10), number of servings of salmon/tuna (canned or fresh) per week (none, <1, 1, >1), whether they ever took cod liver oil at least once per week (yes/no), and use of vitamin supplements (none, supplements without vitamin D, vitamin D or multivitamins).
The researchers found that across all age groups (10-19 years, 20-29, and 45-54 years of age), use of cod liver oil, milk consumption, and salmon or tuna consumption significantly decreased risks of breast cancer. Cod liver oil supplementation produced 56%, 66%, and 37% reduced risks of breast cancer, respectively across the three groups, drinking > 10 glasses of milk per week reduced breast cancer risk by 17%, 40%, and 14%, respectively, and > 1 serving of salmon or tuna per week reduced breast cancer risks by 51%, 19%, and 7%, respectively.
Regarding sun exposure, all variables trending toward increasing sun exposure and thereby increased vitamin D intake resulted in reduced risks for breast cancer. Specifically, spending 30 minutes outdoors between 9 am and 5 pm during the summer months most often reduced risk by 35%, 41%, and 56%, respectively.
For the researchers, “In the present study, results suggest that vitamin D intake early in life influences breast cancer risk.”
Source: Blackmore, Kristina M., Maia Lesosky, Heidi Barnett, Janet M. Raboud, Reinhold Vieth, and Julia A. Knight. “Vitamin D from dietary intake and sunlight exposure and the risk of hormone-receptor-defined breast cancer.” American journal of epidemiology 168, no. 8 (2008): 915-924.
© 2017 Oxford University Press
Posted December 5, 2008.
References:
- “2004/2005 Fact Sheet Cancer Registries: The Foundation for Cancer Prevention and Control” posted on the CDC website.
- Radice D. Breast cancer management: quality-of-life and cost considerations. Pharmacoeconomics 2003;21(6):383-96.
- Blackmore KM. Vitamin D From Dietary Intake and Sunlight Exposure and the Risk of Hormone-Receptor-Defined Breast Cancer. Am. J. Epidemiol. 2008 168: 915-924; doi:10.1093/aje/kwn198.
- Hicks GE. Associations Between Vitamin D Status and Pain in Older Adults: The Invecchiare in Chianti Study. Jou Am Ger Soc 2008; 56(5): 785-791.
- Palmieri C. Serum 25 hydroxyvitamin D levels in early and advanced breast cancer. Clin Pathol. Published Online First: 17 October 2006. doi:10.1136/jcp.2006.042747.
- Knight JA, Lesosky M, Barnett H, et al. Vitamin D and reduced risk of breast cancer: a population-based case-control study. Cancer Epidemiol Biomarkers Prev (2007) 16(3):422–429.