Skip to content

Cancer Health Center

Font Size

Vitamin D May Not Cut Cancer Deaths

Study Shows No Link Between Vitamin D Level and Cancer Deaths -- Except for Colorectal Cancer
WebMD Health News
Reviewed by Louise Chang, MD

Oct. 30, 2007 -- Cancer researchers today reported that blood levels of vitamin D -- whether high or low -- may not help prevent adults from dying of cancer over a dozen years.

But colorectal cancer may be the exception, according to the scientists, who included D. Michal Freedman, PhD, MPH, of the National Cancer Institute.

Vitamin D has attracted attention from researchers for its possible anticancer effects.

Freedman's team studied data on more than 16,800 people aged 17 and older who participated in U.S. health studies between 1988 and 1994.

In those studies, participants got a blood test to measure their blood level of vitamin D.

Freedman and colleagues followed the participants through 2000. During those 12 years, 536 participants died of cancer.

Participants' vitamin D levels at the study's start didn't appear to affect cancer mortality in general, regardless of age, sex, race, or other factors.

However, people with high levels of vitamin D at the study's start were 72% less likely than those with low levels of vitamin D to die of colorectal cancer.

Death rates for the other cancers that were studied, including lung cancer, breast cancer, prostate cancer, other digestive cancers, non-Hodgkin's lymphoma, and leukemia, weren't linked to vitamin D blood levels.

The study's limits include the fact that participants only had their vitamin D level checked once. So it's not clear if their vitamin D level rose or fell over the years.

Freedman's team had lots of data including which participants smoked and exercised. But they can't rule out the possible influence of other factors.

The study appears in next week's edition of the Journal of the National Cancer Institute.

An editorial published with the study states that "the relationship between nutritional factors and colorectal as well as other cancers is complicated" and that the findings "must be put into the context of total diet and lifestyle."

The editorial was written by experts including Johanna Dyer, DSc, RD, of the Office of Dietary Supplements at the National Institutes of Health (NIH).

Today on WebMD

Colorectal cancer cells
A common one in both men and women.
Lung cancer xray
See it in pictures, plus read the facts.
sauteed cherry tomatoes
Fight cancer one plate at a time.
Ovarian cancer illustration
Real Cancer Perspectives
Jennifer Goodman Linn self-portrait
what is your cancer risk
colorectal cancer treatment advances
breast cancer overview slideshow
prostate cancer overview
lung cancer overview slideshow
ovarian cancer overview slideshow
Actor Michael Douglas