Vitamin D for Cancer Defense

vitamin D for skin cancer prevention
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Some research suggests that boosting your levels of vitamin D may help lower your cancer risk. Available in supplement form, vitamin D is an essential vitamin that plays a key role in immune function and helps reduce inflammation. While studies on vitamin D and cancer prevention have yielded mixed results, there's some evidence that people with higher levels of vitamin D may have a decreased risk for certain types of cancer.

The Science Behind Vitamin D and Cancer

To date, most of the scientific support for vitamin D's potential role in cancer prevention comes from observational studies (i.e., studies that examine specific characteristics of a particular population).

In a 2006 report, for instance, investigators reviewed 63 observational studies on vitamin D levels and risk of cancer (including colon cancer, breast cancer, and prostate cancer). According to the report, most of the studies showed that people with ample vitamin D levels had a lower cancer risk.

A number of clinical trials (i.e., studies that test the effects of a certain treatment or health intervention) have also focused on vitamin D and cancer risk. For example, a 2007 study of 1,179 healthy women (all of whom were over age 55) assigned each participant to one of three interventions: one group was given 1,400 to 1,500 mg of calcium daily; a second group was given calcium plus 1,110 IU of vitamin D; the third group was given a placebo.

After four years, those who took both calcium and vitamin D showed a significantly reduced risk for all types of cancer (compared to those who took calcium only or the placebo).

On the other hand, a number of other clinical trials have found that taking vitamin D supplements failed to reduce risk of breast cancer and colorectal cancer (two of the most common forms of cancer in the United States).

Using Vitamin D Supplements for Cancer Prevention?

Given the lack of supporting research, it's too soon to tell whether taking vitamin D supplements can reduce cancer risk. To that end, the National Cancer Institute does not recommend for or against the use of vitamin D supplements to reduce the risk of any type of cancer.

However, since maintaining optimal vitamin D levels is important to overall health, many medical experts recommend increasing your vitamin D intake. Although vitamin D is found in some foods (such as oily fish and fortified milk) and can be produced by the body during sun exposure, taking supplements may be a more reliable means of upping your vitamin D levels.

If you're interested in using vitamin D supplements to boost your cancer defense (or for any other health purpose), talk to your doctor about finding a supplement that's right for you. It's important to note that self-treating a condition and avoiding or delaying standard care or preventative measures may have serious consequences.


American Cancer Society. "Vitamin D". Last accessed October 2010.

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Disclaimer: The information contained on this site is intended for educational purposes only and is not a substitute for advice, diagnosis or treatment by a licensed physician. It is not meant to cover all possible precautions, drug interactions, circumstances or adverse effects. You should seek prompt medical care for any health issues and consult your doctor before using alternative medicine or making a change to your regimen.

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