Once again, the Huffington Post features front page quackery. In this case, it's a ridiculous article that accuses dermatology of being a conspiracy to make doctors rich; you know that stuff about UV damage to the skin inducing melanoma? It's all made up by doctors who are in the pocket of the vast sunscreen industry.
I don't link to Huffington Post anymore, so you'll have to settle for Peter Lipson's deconstruction.
I think the greatest risk of melanoma is heredity, not sun exposure. Having lots of moles puts you at greater risk. Not to defend any medical wooo from Huffpo, but least we all decide to become monks and live in caves, there is quit a bit of controversy in the medical community about the net effects of exposure to the sun. It definitely increase some cancers, but those that are increased are usually the non fatal ones. I remember this Harvard cancer epidemiologist (studies the statistics of disease), based on studies of big populations across the USA, said something like that for every skin cancer death caused by the sun, there were probably something like 20 potential deaths by other cancers that were prevented. Unfortunately I can't find the article right now, but I think it was on Science Daily a few years ago. Of course the dermatologists jump up and down about this, but their view of this subject is only skin deep. In searching for that article I came up with a bunch of other interesting ones about the sun, sun burn, vitamin D, cancer and other health related things.
Males working with high sun exposure get protection from kidney cancer:
Genetics, not sun exposure is more closely associated with melanoma, the deadly type of skin cancer:
Study recommends older people get 2000 iu Vit D per day, if not getting sun:
Low vitamin D levels have many adverse health effects, beyond bones, like increased heart attack risk in diabetics:
Vitamin D deficiency linked to colon cancer and other bowel diseases. Vit. D works with beneficial gut flora(probiotics) to keep a healthy colon.:
There are now genetic tests that allow doctors to asses a person individual risk of skin cancer, due to the discovery of certain markers:
The wikipedia article about sunburn is pretty good. "The statement sunburn causes skin cancer is accurate when it refers to either basal-cell carcinoma, the mildest form of cancer, or squamous cell carcinoma. But the statement is false when it comes to malignant melanoma (see picture: UVR sunburn melanoma)" Melanoma is tied to UV from the sun, but its the total lifetime sun exposure, the free radicals created by sun exposure(amongst many other things in our lives) that increase melanoma risk. Genetics is probably the main risk.:
I remember a professor I had for a graduate course in molecular genetics was telling us about the body's natural gene repair mechanisms. He told us that when we are out in the noon day sun, every cell in our skin was incurring dozens if not hundreds of gene breaks per second caused by the UV light(a distortion called a C-T bridge). Our gene repair mechanisms are so robust that almost all of them are fixed immediately. He said that, although he is not a medical doctor qualified to make clinical recommendations, based on how the gene repair enzyme is stimulated by regular sun light(not UV light), if one ever gets a bad sunburn, the best thing to do might be to go put on a nice heavy dose of sunscreen, and get back out in the sun. This may explain why tanning beds are so bad; you're only getting UV light, not much normal full spectrum light at the same time to stimulate the gene repair. Some medicines and herbs also interfere with the gene repair enzymes.