Does Vitamin D Protect Against Cancer?

According to an article by Peter Russell with WebMD, high levels of vitamin D may be linked to a lower risk of people developing some cancers.  A Japanese based study says the vitamin may be particularly effective at protecting against liver cancer, according to the researchers.

Most of us know Vitamin D as the sunshine vitamin that our bodies produce when our skin is exposed to sunlight.  Some foods also are a source of vitamin D, such as oily fish, eggs and fortified breakfast cereals.  Vitamin D can also be taken as a supplement.

Having a vitamin D deficiency might cause disorders that are associated with weak bones, as evidence may suggest, and may be associated with other diseases as well, including bowel and lung cancers.  It is not well documented if vitamin D is associated with other types of cancers, or cancers overall.

If you are currently taking Vitamin D, it is important to get monthly blood work drawn in order to check your Vitamin D levels. Too much Vitamin D for a certain time can be toxic and harm the liver. Vitamin D is considered a “Fat soluble” vitamin which means if you get too much, it is stored in the liver and can cause great liver damage.

In Europe and America there have been studies.  The BMJ was the latest research that looked at whether the same link might be seen in Asian population.  Data was analyzed from a Japanese health study that involved 33,736 men and women that were ages 40 to 69.  Details of their medical history, diet and lifestyle were provided by the participants.  Through blood samples their vitamin D levels were measured and they were split into 4 groups, from the lowest to the higher levels of vitamin D.  Over an average of 16 years, 3,301 new cases of cancer were diagnosed in the study.  Participants in the quartile with the highest vitamin D levels had a 22% lower risk of cancer compared with those in the bottom quartile.  They did find, however, no association for lung cancer or prostate cancer.

It was noted by the authors that none of the cancers examined did show any increased risk associated with higher vitamin D levels.  After taking into accounts other factors linked to cancer, such as age, weight, physical activity levels, smoking, alcohol intake and diet, the researchers then reached their conclusions.

According to Sophia Lowes from Cancer Research UK, this study suggests that higher vitamin D levels in the blood could mean lower cancer risk in Asian populations, but the over all evidence for a possible link has been mixed.  They aren’t sure if being deficient in this vitamin reflects poor general health or is it having a direct impact on cancer risk.

Just get out there and enjoy the sun, but do so safely.  Be sure to use a protectant on your skin to avoid burning and increasing skin cancer risk.  Most people should benefit from getting vitamin D in the summer from the sun as long as taking reasonable precautions.  Remember, the fresh air is good for you, too!

Dr Fredda Branyon