Sunny News on Cancer? Not Really

I'm beginning to feel like I'm picking on the hardworking folks at Reuter's all the time. But today's report on the link between more sun and less lymphoma needs some clarification. Especially since it begins with this annoying sentence: "At last, some positive health effects of sitting in the sun!"

Bottom line first
Greater exposure to sunlight may reduce risk of some types of lymphoma, a name used to describe a wide variety of cancers that begin in the lymph system.

This study in 50 words or less
German researchers studied over 700 people with malignant lymphomas, and gathered data about their lifestyles, in particular how much they were exposed to the sun via work, outdoor recreation, climate, etc. The risk for some forms of lymphoma was less with more exposure to sunlight (even tanning beds).

Yes, but. . .
As always with studies that find associations but not cause-and-effect, the implications are limited. This study does not prove that exposing yourself to the sun will lower your lymphoma risk. Exposure to sunlight may be a marker for some other aspect of lifestyle that was not measured in this study.

So what are you going to do about it?

• Nothing. If you're looking for good reasons to make like George Hamilton, you're not going to get it from The Truth Squad--or the International Journal of Cancer, for that matter.
• Still, realize that lymphoma (about 19,000 deaths this year) kills more than melanoma (about 8,000 deaths). More cancer data here.
• There is a very interesting issue about whether Americans are low in Vitamin D--due in part, perhaps, to our decreased exposure to the sun, thanks to more SPF 30 and skin cancer awareness generally. (Vitamin D is manufactured by the human body when the skin is exposed to the sun; it plays an essential role in immune function.) Of course, dermatologists hate this, because they fear people will go out and get more skin cancer if the stay-out-of-the-sun message gets blurred. There's an excellent article on the Vitamin D/skin-cancer hoo-ha here.
• The non-hysterical view appears to be that healthy people can expose, say, their arms or legs to up to 10 minutes of sun most days to make sure they have plenty of Vitamin D without extra melanoma risk.