Wednesday, June 13, 2007

Can a daily dose of sunlight prevent cancer?

According to this summary and proponents of vitamin D, yes your risk of cancer (and many other diseases) can be significantly reduced with normal levels of vitamin D.

But what does that have to do with sunlight, you ask?

Good question. After all, cancer institutes, dermatological societies and even sunscreen manufacturers extoll the benefits of sunscreen and limited exposure for skin health. Skin cancer is dangerous and can be fatal. So if sunlight is the main culprit, how can it be helpful?

Our bodies make vitamin D when exposed to the sun. In fact, significant rises can be seen in as little as 15-20 minutes.

But there is a catch...

Get a daily dose without blocks vitamin D production.

How much exposure? At least 15 minutes and some say up to 1 hr. Any more than that and you will need the sunscreen.


Anonymous said...

Thanks for posting this, with a great reminder that a small amount of sensible sun exposure can play a role in a cancer prevention lifestyle. In the U.S. it is estimated that roughly 24,000 people die from cancer each year due to lack of sun exposure (presumably secondary to lack of vitamin D). This is more than twice the number of people that die from skin cancer. After this fifteen minutes or so outside, make sure to apply a sunscreen that protects against UVA rays as well as UVB rays. Formulations that cover these include ingredients such as mexoryl SX or helioplex. The risk of melanoma in 1935 before sunscreen was available was one in 1500. It is one in 84 now, and some researchers feel that sunscreen that only protects against UVB rays may provide a false sense of safety.

Lynne Eldridge M.D.
Author, "Avoiding Cancer One Day At A Time"

brian said...

Thanks for your comments and thanks for reading. Your point regarding UVA and B is well-taken.

The statistics you site regarding risk are remarkable. For the risk to increase so much in 70 years, there's got to be more to it than continued exposure to UVA rays, don't you think?

Brian Sekula, Ph.D.