February 26, 2007

Vitamin D protects against Breast Cancer & curbs tumour progression

Vitamin D from the SunWritten by Kevin Flatt

Natural Sunlight Destroys Breast Cancer Tumours: “…the cells treated with Vitamin D fared much better. And while the vitamin protects healthy cells, Rebecca Mason’s experiments are showing that vitamin D has the opposite effect on cancer cells. It kills them.” - Professor Michael Holick.

Exposure to sunlight is the greatest source of vitamin D and population studies have previously suggested higher vitamin D levels may contribute to the lower incidence of breast cancer seen in sunny climates such as the Mediterranean.

The idea that vitamin D may play a useful role in helping to prevent breast cancer was given a boost by UK research presented in March 2004. The researchers announced at a British Endocrine Societies meeting that they had found an enzyme in breast tissue that converts vitamin D into a cancer-fighting compound called calcitriol. Until now, it had been thought that this enzyme was only present in the kidneys.

Not only does the active form of vitamin D, calcitriol (the form made in optimal quantities by your body when your vitamin D blood levels are ideal) inhibit breast cancer cells from growing, it makes those cells grow and die more like natural cells. Furthermore, vitamin D inhibits the formation of excessive blood vessel growth around the cancerous tumour, a process called anti-angiogenesis. (Braz J Med Biol Res. 2002 Jan;35(1):1-9).

In the 1990’s, scientists from the University of California at San Diego provided the first evidence of how many women may be dying needlessly from breast cancer due to low vitamin D blood levels. The researchers measured the amount of sunlight available to the women at the latitude where they lived and combined that with the frequency of cloudy weather. Sunny climates are associated with higher vitamin D levels. They found that women in the sunniest regions of the USA were about half as likely to die from breast cancer as were women who lived in less sunny regions. When the same researchers looked at the USSR, before that country dissolved, they found that women who lived in the sunniest regions were three times less likely to develop breast cancer than were the women who lived in regions without as much sun. (Prev Med. 1990 Nov;19(6):614-22 and Int J Epidemiol. 1990 Dec;19(4):820-4.).

Researchers in Toronto interviewed 576 patients who had been diagnosed with breast cancer and 1,135 women who had no breast cancer. They found a direct connection between reduced breast cancer risk and exposure to sun as an adolescent. Women who worked an outdoor job between the ages of 10 and 19 had an estimated 40 percent reduced risk of breast cancer, and women who participated in frequent outdoor activities between the ages of 10 and 29 lowered their breast cancer risk by an estimated 35 percent. One of the researchers said: “What you are exposed to during breast development may be particularly important in determining future breast cancer risk. Current thinking is that exposures during adolescence or before a full-term pregnancy may have a greater effect, as that is when breast tissue is going through the most rapid development.”

In 1999, researchers at the Northern California Cancer Center and the University of Miami, followed 5009 women for 20 years, as part of a large NHANES I study. 190 of the women subsequently developed breast cancer. The researchers did not have calcidiol blood levels available, so they looked at many markers of vitamin D levels, such as living in sunny climates, sun damaged skin (indicted past sun exposure), a history of occupational and recreational sun exposure and dietary vitamin D.

All of these factors reduced the risk of breast cancer. Dietary vitamin D reduced the risk a little (due to the tiny doses of vitamin D consumed) but women with high occupational and recreational sun exposure who lived in a sunny climate reduced their risk three fold. Remember, 90 % of our vitamin D comes from sun exposure. Vitamin D from diet and supplements is close to insignificant due to the small amounts consumed. (Cancer Epidemiol Biomarkers Prev. 1999 May;8(5):399-406).

Medical News Today reported on 18 Sep 2005 that Scientists reporting in the journal Photochemisty and Photobiology estimated that about 50,000-63,000 annual cancer deaths in the U.S. (10% of all cancer deaths) could be prevented if all Americans had sufficient vitamin D. These findings are based on data in the Atlas of Cancer Mortality Rates for the United States, , (cancer.gov/atlasplus/type.html), but are also supported by a number of recent reports that vitamin D plays a very important role in increasing survival once cancer is discovered. These deaths greatly outnumber the annual number of deaths from melanoma (8000) and skin cancer (2000). (Medical News Today 18 Sep 2005).

For example, solar UVB irradiance has been shown to be inversely correlated with breast cancer in ecologic studies in Canada, the former Soviet Union, European countries and the United States. Guidelines regarding sunscreen use might also be changed, because sunscreen preferentially absorbs UVB radiation and thus markedly impairs vitamin D production (SPF 8 can reduce vitamin D production by 95%). Public health advisories to minimize solar UVB irradiance, especially when given without any additional guidelines for the importance of vitamin D, could be more harmful than beneficial to public health, especially because the primary vitamin D source for many people is solar UVB irradiance. (Photochemistry and Photobiology: Vol. 81, No. 6, pp. 1276–1286).

Another Medical News Today article released on 17 Oct 2006 reported on a study published ahead of print in the Journal of Clinical Pathology, demonstrating that Vitamin D may help curb breast cancer progression.

The article reported that the authors reached their conclusion from a study of 279 women with invasive breast cancer. The disease was in the early stages in 204 women, and advanced in the remainder. Serum levels of vitamin D, parathyroid hormone, and calcium were measured in both groups of women. The results showed that women with early stage disease had significantly higher levels of vitamin D and significantly lower levels of parathyroid hormone than did the women with advanced disease. The article also noted that laboratory studies have also shown that vitamin D stops cancer cells from dividing and that it enhances cell death. And the epidemiological evidence (population studies) points to a link between rates of, and deaths from, breast cancer and exposure to sunlight. (Medical News Today 17/).

In 2004, a group at the University Hospital in Quebec confirmed that vitamin D, especially when taken with calcium, significantly reduced abnormal mammograms. In fact they found women with the highest vitamin D intake had only one fourth as may abnormal densities on their mammogram as did women with the lowest intake. (Cancer Epidemiol Biomarkers Prev. 2004 Sep;13(9):).

Leading vitamin D researchers are suggesting that the optimum adult level seems to be 4,000 daily units which is 20 times the government level for those 50 and under. The government says 2,000 is the limit for all ages before side-effects result. The researchers disagree and say amounts considerably above 2,000 units may be warranted when considering the multitude of potential benefits. (CBN News 10/1/2007).

Make sure you’re taking D3. If the label says vitamin D2, then it’s not the good kind of vitamin D. So often, you see orange juice or foods that say they’re vitamin D fortified. But many times, those are fortified with D2. Vitamin D has to be taken with fat. Taking a vitamin D pill with orange juice isn’t going to work, it won’t absorb.

Try to get brand-name recommendations. Sadly, many doctors haven’t learned about supplements in medical school, so your doctor may not be able to advise you on that. To find the best brands, do your homework. Either get names of products from people you trust, or go on the Internet and look these supplements up.

Typically, dieticians say the best source of vitamins is through the foods we eat, rather than supplements. But Judy Carr, a registered dietician and certified diabetes educator says the best food sources of vitamin D aren’t necessarily the foods we love. In December, after reading a little more about the vitamin, Carr asked her doctor to include a vitamin D analysis with her routine blood work. She was surprised when her results came back showing her levels were on the low end of normal. “I’m thinking if that’s me, because I don’t have a horrible diet, I can’t imagine what the general population’s is,” Carr says. (Denver Post 14/2/2007).

Dr. Michael Holick, a leading vitamin D researcher who serves as director of the general clinical research center at Boston University Medical Center, said it’s difficult to get enough vitamin D from food, noting that you’d have to eat a 3½-ounce serving of fish like salmon, mackerel or sardines “almost every day just to begin to satisfy your requirement.”

The NIH agrees: It can be difficult to obtain enough vitamin D from natural food sources. For many people, consuming vitamin D fortified foods and adequate sunlight exposure are essential for maintaining a healthy vitamin D status. In some groups, dietary supplements may be needed to meet the daily need for vitamin D.

A tablespoon of cod-liver oil contains more than 1,300 IUs. Salmon (360 IUs for 3.5 ounces), sardines (250 IUs for 13/4 ounces) and fortified milk (about 100 IUs per serving) are also good sources.

No matter what cancer you have, or are trying to prevent, the real question is should cancer patients be left vitamin D deficient? Many experts will tell you that vitamin D should not be taken for breast cancer until well controlled scientific studies prove it helps. The problem with that approach is two-fold. First, you may die waiting for the studies to be conducted and two, it misses the point. The point is this: women with breast cancer should not allow themselves to be vitamin D deficient and neither should their doctors. (vitamindcouncil.com).

Finally, I’ve always thought that it’s pretty significant that the parts of the body least exposed to the sun are more likely to experience a malignant melanoma.

But a new look at 528 melanoma victims over five years also found that increased sun exposure led to increased survivability, according to the study led by Marianne Berwick of the department of internal medicine at the University of New Mexico. “It’s totally counterintuitive, and we’re trying to investigate it,” said Berwick, who is doing a similar study of 3,700 melanoma patients worldwide. “It’s really strange, because sunburn seems to be one of the factors associated with improved survival.” (The Baltimore Sun 2/2/2005).

Related articles:
Cancer (General) Articles and News

The Multitude of Health Benefits from Natural Sunlight and Vitamin D

Breast Cancer Progression Correlates with Lower Vitamin D Levels



William B. Grant, Cedric F. Garland and Michael F. Holick. Comparisons of Estimated Economic Burdens due to Insufficient Solar Ultraviolet Irradiance and Vitamin D and Excess Solar UV Irradiance for the United States. Photochemistry and Photobiology: Vol. 81, No. 6, pp. 1276–1286.

Garland FC, Garland CF, Gorham ED, Young JF. Geographic variation in breast cancer mortality in the United States: a hypothesis involving exposure to solar radiation. Prev Med. 1990 Nov;19(6):614-22.

Gorham ED, Garland FC, Garland CF. Sunlight and breast cancer incidence in the USSR. Int J Epidemiol. 1990 Dec;19(4):820-4.


Bortman P, Folgueira MA, Katayama ML, Snitcovsky IM, Brentani MM. Antiproliferative effects of 1,25-dihydroxyvitamin D3 on breast cells: a mini review. Braz J Med Biol Res. 2002 Jan;35(1):1-9.

John EM, Schwartz GG, Dreon DM, Koo J. Vitamin D and breast cancer risk: the NHANES I Epidemiologic follow-up study, to 1992. National Health and Nutrition Examination Survey. Cancer Epidemiol Biomarkers Prev. 1999 May;8(5):399-406.

Berube S, Diorio C, Verhoek-Oftedahl W, Brisson J. Vitamin D, calcium, and mammographic breast densities. Cancer Epidemiol Biomarkers Prev. 2004 Sep;13(9):.


Copyright 2007 KevinFlatt. Disclaimer: The information contained in this article is presented for information purposes only and is in no way intended to replace professional medical care or attention by a qualified practitioner. It cannot and should not be used as a basis for diagnosis or choice of treatment.

Copyright 2007 Kevin Flatt. Reproduction of any information on other websites is PROHIBITED.

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