Vitamin D, UV-B Sunlight and Gallbladder Cancer

While wandering about the internet, I discovered an article about sunshine, UV-B sunlight in particular, Vitamin D, and cancer. Not just gallbladder cancer, but a number of cancers, especially those of the gastro-intestinal tract. Having found the one article, I have found some other articles on this topic. I've thought of myself as pretty well informed on health issues generally, but I don't remember reading any of this in my pre-cancer days.

Entitled "Solar ultraviolet-B exposure and cancer incidence and mortality in the United States, 1993–2002," the full text of the article that got me thinking about this is available online for those who want more information. The gist of this research, which uses data of 3 million cancer diagnoses from 1998 to 2002, and 3 million cancer deaths from 1993 to 2002, is that some cancers are more prevalent in areas of the country where people are less likely to have exposure to UV-B sunshine, and thus less likely to have good levels of Vitamin D. And, most important to me, this is true for women (but not necessarily men) with gallbladder cancer. If you are reading this and affected by another cancer, it's worth reading the long list of cancers in the study that the authors describe as impacted by lack of Vitamin D.

Let me try to say this more clearly (because goodness knows, the article has lots of technical medical language in it). Because parts of the U.S. are far enough north that even if we are outside during the winter months, we do not get enough UV-B sunlight to make the Vitamin D we need to have sufficient amount in our bodies. In another article this week, I read that the minimum daily requirement for Vitamin D was established by the government as a minimum to prevent rickets (early 1900s), and certainly it did not anticipate that many of us would spend our days indoors as well as be living too far north to benefit from the sunshine.

You may be wondering how all of this fits into the dermatologists' campaign over the last years to see that all of us wear our sunscreen outside. I'm not a doctor (as most of you reading this know), but I have heard even dermatologists say publicly recently that we should all be getting about 20 minutes of sunlight on our unprotected skin each day to ensure adequate amounts of Vitamin D in our bodies. So, I think that even with their worry about melanoma, they are recognizing that getting some sunlight is valuable. But after that 20 minutes, they want us to put the sunscreen on and restrict our exposure to the intense mid-day sun.

So, back to this study. Another aspect to this study is that while we can take Vitamin D supplements, there is actually some evidence that getting the sunshine, UV-B rays particularly, and making our own Vitamin D, is actually preferable to the supplements.

It seems that gallbladder cancer in women is statistically linked to insufficient sunlight exposure. As a result, I have purchased a "sun lamp" with UV-B rays, and when it arrives next week, I'm ready to use it the prescribed 20 minutes each day. Maybe it will slow the progression of the disease (which the article suggests sufficient UV-B exposure, and Vitamin D might), and maybe it won't. But I'll at least have a better mood through the dark winter days of Massachusetts, and maybe I'll even look a little tanned, instead of pasty! And, thinking back to the summer months immediately following my diagnosis, I am remembering how much time I spent outside, in the sun, wearing sunscreen, but not being obsessive about it, since I was no longer worried about skin cancer as much as I was about surviving gallbladder cancer for as long as possible. So, maybe the summer sunlight slowed the progression of the disease, and maybe my sunlamp will help now, too.

With this posting, I am thinking it's time to put a "This is not medical advice" warning on my blog. First, I have to figure out how! Thanks for reading.