This story sensationalizes and inaccurately presents new research indicating that low blood levels of vitamin D at the time of breast cancer diagnosis are associated with poor prognosis. The information presented by the experts interviewed does not address any of the important scientific details of the research on which the story was based. The expert comments do not provide any interpretation of the research results or what they mean for women with breast cancer. The final comments by one of the cancer researchers interviewed -“I was very surprised at how low my vitamin D levels were. I thought I was doing everything right.” – are misleading. These comments are more hype than substance. For the story to conclude with the host saying, "Now with daily vitamin D supplements, she just might be", gives the false impression that women who are not taking vitamin D supplements are doing something wrong. Overall, this story is short on accurate information and based on inferences and speculation.
For the story to conclude with a promotion of daily vitamin D supplements, based on the results of this recent abstract, is potentially harmful.
The cost of vitamin D supplements (unspecified amount) was cited as "just pennies a day." However, vitamin D is not currently used as a treatment for breast cancer.
The quantification provided in the story "…women deficient in vitamin D were 94% more likely to have their cancer spread and 73% more likely to die from their cancer" is inappropriately portrayed. There is no mention of the comparison group (women with adequate levels of vitamin D), or that the time frame is approximately 10 years.
No potential harms of taking vitamin D are mentioned. The headline says "Take your vitamin D" but provides no information on how much vitamin D is recommended or how much can be harmful. In healthy people the toxic effects of taking excess vitamin D include too much calcium in the blood, irregular heart beats, kidney stones, and gastrointestinal symptoms. It is unknown whether there are other harmful effects in cancer patients.
The "headline" promoting this story is neither accurate nor evidenced-based. Virtually all relevant information regarding the research on which is was based was not provided. The story neglected to mention that it was based on preliminary prospective research that followed women with newly diagnosed breast cancer for 10 years. The objective was to determine if the level of vitamin D in their blood when they were diagnosed with cancer were associated with their long-term prognosis: distant disease free survival and overall survival. The story really should have emphasized that the researchers were reporting an association between vitamin D deficiency and breast cancer progression, rather than suggesting that it causes cancer. The story would incorrectly lead one to believe that the women were given vitamin D supplements. The results that vitamin D deficient women were almost 2 times as likely to have their cancer spread was accurately reported. Information indicated that they were 73% more likely to die left out important information that percentage was lessed or absent depending on the specific characteristics of the cancer. Non-disclosure of fact that the experts interviewed were not involved in the research was another significant omission.
Unfortunately, this story capitalizes on a complex and serious cancer that can have devastating effects on women affected and their families. The story frames "vitamin D deficiency" as a cause of breast cancer, and exaggerates the potential harms associated with a low vitamin D level. The story that plays on emotion by giving false hope that taking vitamin D can help to fight breast cancer. Vitamin D may be a therapeutic option in the future, but current knowledge to support this claim is lacking.
This article makes no mention of the source of the information, a research abstract that will be presented at the American Society of Clinical Oncology Annual Meeting (May 30-June 3, 2008). It neglect to mention that none of the experts interviewed for this story were involved in the research. However, since it did use several different sources, we’ll give the story the benefit of the doubt on this criterion.
This story does not provide basic information on treatment options for breast cancer except to mention the "established drug Tamoxifen." What it does present is inaccurate, "The effects of vitamin D on breast cancer cells are very similar to the effects of the established drug Tamoxifen." This overstates what the research on vitamin D and breast cancer in its early stage. The graphic described as "This is a cluster of human breast cancer cells. Now add vitamin D and those cancer cells start to shrivel up and die" is completely inappropriate and simplistic.
Vitamin D, a fat-soluble vitamin that is is essential for bone development and health, is readily available as a dietary supplement.
The research on which this story is based makes an important contribution to the growing body of scientific evidence which indicates that blood levels of vitamin D maybe associated with breast cancer prognosis. This story mis-states and overstates the novelty of this treatment.
Because several sources were used, we can assume that the story did not rely solely or largely on a news release.