There have been studies showing that that rates of all types of skin cancer have been increasing over the past few decades. I have no reason to doubt this.
However. We’ve had effective sunblock for about seventy years or so; before that we had no real means of effectively blocking UVA or UVB radiation from the skin. Go back to pre-industrial times, and a lot more people are going to be spending a lot more time outside, because in a pre-industrial society there really weren’t that many office jobs. If I’m a typical joe in 1680, chances are I’m going to be spending the entire summer out working in the fields, tending to the chickens, whatever my subsistence agrarian lifestyle requires. So is my family.
So why weren’t rates of particularly non-melanoma skin cancers (as I understand that low-level, prolonged exposure increase the risk of non-melanomas more) absolutely massive by comparison?
Obviously, your 17th century barber isn’t going to identify that weird growth on someone’s face as basal cell carcinoma, so is it merely an issue of nothing having been recorded as skin cancer? Is it possible that there was a dramatically higher rate but it’s hard to prove (as that was still a long ways away from what we consider epidemiology)?
Didn’t most people in 1600’s, even through the 1800’s wear full clothing? Hats also seemed to be common, most outside workers typically would wear long sleeves to aid in cooling.
Don’t know about ancient but for say 1400 on my vote is on the fact that even plowing, you didn’t expose that much skin. Hats, long sleeves as a rule – had to count for something.
That, and when people did get leisure time they didn’t make it a point to strip nearly naked and back in the sunlight. People tended to wear more clothing, cover up, some cosmetics used back then were thick enough to probably act as a sunblock to some degree…
People died of a lot of other stuff back then, often at what we’d consider a young age. It’s possible quite a few of them had skin cancer at the time they died but it wasn’t what killed them.
My google-fu is failing me tonight - how does say the Amish community compare to the US as a whole in skin cancers? If its significantly lower (say 50%) we could be onto something.
I understand the surface logic of this, but a wool or cotton shirt doesn’t do a whole lot to protect against UV radiation. It’s a better barrier than nothing, of course, but I don’t imagine it would have held up very well against long-term exposure.
Small protection over the long term is going to be better than no protection over the long term. Also note the bit about not baking oneself as a form of recreation.
The explanation is likely a number of factors whose influence adds up over time.
Note that the same is true nowadays for agricultural workers in less developed countries. This is the typical garb of workers in rice paddies across south east asia. Long flowing sleeves and big hat, there is no skin exposed to the sun at all:
I recall reading something that Coco Chanel, French fashion designer, was the person who popularized the suntan as a facet of the luxury lifestyle somewhere around WWI. Before that a tan was associated with peasantry toiling in the fields (at least, hands and face) and lily-white skin was a mark of the aristocrat who never had to go out and work in the sun. Of course, all that changed with the industrial revolution anyway, and mere factory workers sported that aristocratic fish-belly look; which would therefore make basking in the sun the mark of luxury.
From what I’ve read, the vast majority of skin cancer deaths are from melanoma, but the vast majority of skin cancers are not melanoma.
So 2% of skin cancers make up 75% of deaths, the other 98% make up the other 25% of deaths.
I don’t know the terminology well, but I have no idea what % of that 2% is ‘malignant melanoma’. It could be a fraction of 1% of skin cancers that cause 75% of deaths.
Most skin cancers (particular basal cell carcinoma) advance at a relatively slow pace, and in “pre-industrial” times, by the time they got large enough to be more than disfiguring and become a threat to life, the patient may well have died of something else.
We don’t have too good a handle on skin cancer incidence rates long ago, because diagnosis wasn’t very reliable. It’s been estimated for instance that only a small fraction of supposed leprosy cases in the Middle Ages were actually due to Mycobacterium leprae. Most of the unfortunates who were killed or herded into sanitariums probably had noncontagious inflammatory skin disorders, or skin cancer.
Lifestyle factors in ancient times differed considerably from current ones. I’m pretty sure that peasants in the 14th century didn’t spend a lot of time soaking up sun at the beach or using tanning beds.
