California bans minors from using tanning beds

California just banned the use of tanning beds by minors.  What's next, shutting down the beaches on sunny days?

I'm exaggerating a little bit.  Tanning beds don't emit the same UV wavelength and intensity as natural sunlight -- so I suppose there's a technocratic public health case to be made -- but at the same time, in a sunny state like California (well, Southern California), there are plenty of opportunities to burn yourself naturally.

But it's far from clear that tanning bed usage is a primary driver in the rise in melanoma and non-melanoma skin cancer.  I have been searching the website of Ted Leiu, the State Senator sponsoring the legislation, for the scientific papers that make him so confident:

• "If everyone knew the true dangers of tanning beds, they’d be shocked."
• “Other scientific research has shown conclusively that use of tanning beds causes skin cancer, and the younger kids are when they start using tanning beds, the greater the cumulative damage to their skin and the more likely they are to die of skin cancer.”

After much digging, I found a frequently cited statistic ("those who use tanning beds before age 35 increase their lifetime risk of melanoma by 75 percent") pointed back to this meta-study: "The association of use of sunbeds with cutaneous malignant melanoma and other skin cancers: A systematic review".

This is from the abstract:

"Based on 19 informative studies, ever-use of sunbeds was positively associated with melanoma (summary relative risk, 1.15; 95% CI, 1.00–1.31), although there was no consistent evidence of a dose–response relationship. First exposure to sunbeds before 35 years of age significantly increased the risk of melanoma, based on 7 informative studies (summary relative risk, 1.75; 95% CI, 1.35–2.26)."

So ever-use of tanning beds based on 19 studies showed a minimal increased risk (15%), with no dose-response relationship -- which is rather odd, given that you would expect more tanning sessions to lead to a greater incidence of melanoma, right?  In the group of 7 studies that looked at age of first exposure, the relative risk was 75% higher.

Sounds big, doesn't it?

Not when you start looking at other risk factors of melanoma (which they didn't do in the meta-study).  I blogged last year about a new paper that tied melanoma to tanning bed usage.  In that study, the risk factor for ever-use of tanning beds was 74% (higher than the 15% in the meta-study just mentioned).   But this 74% higher risk from tanning beds was exceeded by blonde hair (117%) and dwarfed by red hair (253%), very fair skin (450%), and having moles (1,281%).

That's a huge flaw in this research -- it doesn't focus on the most important risk factors to help us understand the phenomenon of skin cancer, it is out to prove a point about a pet cause: tanning beds.

Another flaw is that few of these studies ever mention any of the benefits of sun or -- heaven forbid -- tanning salons.  Shouldn't California at least go through a cost-benefit analysis?  Are there other types of cancer that might be decreasing with UV exposure?  Maybe so, maybe not -- but don't you think we should look?

Furthermore, the law applies equally to fair-skinned and dark-skinned people (as laws should), but this completely neglects that fact that the cost-benefit trade-off will likely vary substantially based on skin color.  Black adolescents are one of the groups with the highest vitamin D deficiencies in the country (need citation) and black people have dramatically lower rates of skin cancer -- does this ban benefit them?  That said, black people don't go to tanning salons as much as white people do -- but that's not to say they wouldn't benefit from greater UV exposure.

Here's a brilliant solution for our omniscient nanny-state: white adolescents should be banned from tanning salons, but black adolescents should be forced to go to tanning salons.

You see how ridiculous this is?  It's what happens when do-gooder politicians marshal bad (or incomplete) science to attack unpopular, "sinful", or "frivolous" industries.  I understand that this is focused on minors, but states and countries are getting more and more aggressive with these sorts of things.

All this neglects the broader point that people should have the choice to live as they see fit, as long as they aren't harming anyone else.