Introduction
Recent studies have shown that almost all women diagnosed with breast cancer are also vitamin D deficient. In this article, we explore the science behind this link, the impact of vitamin D on breast cancer risk, and what women can do to boost their vitamin D levels and potentially reduce their risk of developing this disease.
Daily Requirements Of Vitamin D
The Recommended Dietary Allowance (RDA) of vitamin D
| Age | Female | Male |
| 0-18 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| 19-70 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| >70 years | 20 mcg (800 IU) | 20 mc (800 IU) |
| Pregnancy | 15 mcg (600 IU) | |
| Lactation | 15 mcg (600 IU) |
Vitamin D Sources
The body can make vitamin D from direct sunlight when outdoors.
It is also obtained through food sources like oily fish, egg yolks, red meat, mushrooms, and fortified cereals.
Connection Between Vitamin D and Breast Cancer
The link between vitamin D and breast cancer risk revolves around the VDR gene.
This gene produces a protein called the vitamin D receptor, to which the active vitamin D binds.
Mutations or changes in this gene affect vitamin D levels in the body.
According to a research review, the same changes in the VDR gene were found to increase breast cancer risk.
Many studies supporting this link have reported that many people were vitamin D deficient when diagnosed with breast cancer.
A review published in The Breast reported that up to 96% of breast cancer patients are deficient in vitamin D.
Further, some studies also suggest that low vitamin D levels are associated with a higher risk for breast cancer recurrence and metastasis.
Does Vitamin D Increase Estrogen?
According to a year-long study, those with the highest levels of vitamin D had the most drop in estrogen levels.
Vitamin D deficiency can lead to estrogen dominance.
This study suggests that vitamin D can be an alternative to estrogen-lowering drugs.
Why Does Vitamin D Deficiency Cause Breast Cancer?
Low vitamin D levels are associated with a higher risk for breast cancer.
This sunshine vitamin helps regulate breast cell growth.
There’s also a direct association between vitamin D and a gene involved in tumor growth and spread called ID1.
According to a study, circulating vitamin D levels are inversely associated with ID1 protein levels.
Thus a vitamin D deficiency may favor breast cancer cell growth.
Can Meeting Vitamin D Requirements Help Prevent Breast Cancer?
There’s no one foolproof way that guarantees breast cancer prevention.
However, by meeting your vitamin D requirements, it is possible to lower your risk for breast cancer.
According to a 2015 study, women or people assigned female at birth who are deficient in vitamin D had a 27% higher risk for breast cancer than those with adequate vitamin D levels.
Another pooled analysis reported that a serum 25(OH)D level of 47 ng/ml was associated with a 50% lower risk of breast cancer.
Thus, meeting your vitamin D needs can help significantly reduce breast cancer risk.
How Much Vitamin D Should I Take For Breast Cancer?
10-30 minutes of midday sunlight several times a week, along with a dietary intake of more than 400 IU of vitamin D/day, can help reduce breast cancer risk and recurrence.
How To Meet and Maintain Vitamin D Requirements?
Though sun exposure and diet are excellent sources of vitamin D, most people can’t get enough of this vitamin.
Due to various reasons like latitude, skin tone, and lifestyle, adequate sun exposure for our bodies to synthesize vitamin D doesn’t happen.
Further, not all countries have dairy products fortified with vitamin D.
In these situations, a high-quality vitamin D supplement can help you be vitamin D sufficient.
Disclaimer: Vitamin D supplements are not advised to be taken without a doctor’s advice. Consult a qualified practitioner for dosage recommendations.
Summary
Vitamin D plays a role in regulating breast cell growth.
Changes in the VDR gene that increase vitamin D deficiency risk also seem to increase breast cancer risk.
Further, lower vitamin D levels are associated with higher protein levels that play a role in cancer cell growth and spread.
Adequate sun exposure, fortified foods, and a quality D3 supplement are effective ways to meet your vitamin D needs.
References
- https://www.breastcancer.org/risk/risk-factors/low-vitamin-d-levels
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5510119/
- https://www.cancer.gov/news-events/cancer-currents-blog/2016/vitamin-d-metastasis
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5802611/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3115047/
- https://www.cancer.gov/news-events/cancer-currents-blog/2016/vitamin-d-metastasis
- http://journals.lww.com/menopausejournal/Pages/currenttoc.aspx
- https://med.stanford.edu/news/all-news/2016/03/vitamin-d-deficiency-contributes-to-spread-of-breast-cancer.html
- https://pubmed.ncbi.nlm.nih.gov/26037255/
- https://pubmed.ncbi.nlm.nih.gov/21868542/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5802611/
