I've known about the sunscreen misinformation for a long time.
My dad died of malignant melanoma. He wore sun screen all the time. He didn't swim. He would wear sun hats. He was paranoid, and likely had premonition of it. Unfortunately, his prevention methods might have actually exacerbated his odds even further because he was depriving his skin of one of its few natural healing modalities.
I'm sorry to hear you dad died of melanoma. But I can guarantee that reducing his UV exposure did not increase his risk. It's possible that intense and closely repeated sun exposure as a child had already caused DNA damage.
You're right, my father had bad sunburns as a child. Shades and hat are a good tip, as is reducing UV over-exposure.
My point is that moderate sun exposure is healthy and good melanoma prevention. From what I've seen, there is quite a bit of research to back this up.
I think that better education about this would encourage people to develop healthy relationships with the sun at a young age. Right now the conventional wisdom seems to be "just throw sunscreen at it" / "stay out of the sun unless you are wearing sunscreen" and I think this totally misses the point.
My caution is that it's unwise to tell people to avoid sun exposure in total. While sunscreen does seem to be helpful in slowing sun damage, it'd also be unwise to suggest that sunscreen will protect people from overexposure, there isn't really evidence for that. There is a whole body of research. Take a look at some of the studies cited in this article http://m.jabfm.org/content/24/6/735.full
I know you probably meant that as a comment about correlation vs. causation, which is understandable. I agree that this is a complex issue, and that there are more factors than just sun exposure. But just so you're aware, your analogy rubbed me the wrong way. My father's death was definitely related to sun exposure in some way or another, and probably other factors like diet (he ate a lot of sugar), psychology/hormones (he experienced a lot of stress), and yes, genetics.
There is misinformation about sunscreen. I'm not going to go and advocate that people don't use sunscreen, rather, for my own self, I've decided that it's important to have positive, moderate exposure to the sun in order to develop a healthy tan, to avoid overexposure, and to use sunscreen and protective clothing if I'm sure to be out in heavy sun.
It's a complex, dynamical issue and there is conflicting evidence about the effectiveness of sunscreen to just blanket reduce melanoma: https://www.ncbi.nlm.nih.gov/pubmed/22994908
Not only that, there have been some controversies about sunscreens themselves containing questionable ingredients, some of which might actually be carcinogenic. If you're going to market your product as cancer preventative, but go and put carcinogens into that very same product, my trust level in your industry has been reduced by somewhere in the range of 25%-75%.
Somehow, in all this, there are people who think any raw sun exposure is going to cause cancer. That's actually misinformation. Melanin is known to be a protective. How can one go about increasing melanin? By tanning in moderation, letting your skin adapt to the sun. Of course there are people who simply don't tan easily, and yes, they should be cautious. But I'm fortunate to have skin that tans, and I'm going to let it do that!
You are misrepresenting the studies findings. It did not show that sunscreen itself is ineffectual, but that as a population measure for children that it's effectiveness was variable. Anyone who has children will attest to the difficulty of applying and maintaining the required level of sunscreen, especially as it is invisible.
If you have concerns about the chemical sunscreens, please use zinc oxide. It is totally non reactive.
Sun damage is cumulative, a tan is a reaction to damage. People with a tan have sun damaged skin.
Naturally very dark skinned people are different, and also have enhanced mechanisms to allow damaged cells to self-euthanize.
Not quite right? A tan is a reaction to sunlight, independent of damage.
Ah! Research, gotta love it. UVA darkens directly as a result of action on the melanin. UVB damages DNA resulting in long-lasting production of more melanin.
Right, it concluded "there is still no evidence of a protective effect of sunscreen against MN development in children". Melanocytic Nevi are precursors to melanoma, and childhood sunburns give people an early start in developing them.
Here's another study arguing that sunscreen might inhibit the inflammatory response without actually reducing the burn. Their abstract concludes "As such, sunscreens might promote instead of protect against melanoma." : http://journals.lww.com/melanomaresearch/Abstract/2005/02000...
SPF is actually measured by reduction of redness. That study points out that reduction of redness doesn't necessarily come with a reduction of damage!
If people are preventing their body from expressing its natural sun defenses and going out and overexposing themselves to the sun, believing themselves to protected... If that protection is illusory, that's kind of a recipe for disaster. People could be getting burned and not even know it... They won't even know to put aloe on.
Take that one with this one, which postulates that sun exposure isn't what causes malignant melanoma, sunburns are:
> Although there is convincing evidence that nonmelanoma skin cancer is related to cumulative sun exposure, there is less evidence of that association with CMM. If CMM were related to cumulative sun exposure, one would expect that outdoor workers would have a greater incidence of CMM than indoor workers. However, that is not the case. The incidence of CMM is actually increasing among indoor workers who receive three to nine times less solar UV radiation than outdoor workers. Furthermore, there is a higher incidence of CMM among whites living in northern states such Delaware, Vermont, and New Hampshire (>30 per 100,000), which enjoy less year-round sunlight and UV radiation than southern states such as Texas, Florida, Arizona, and New Mexico (<25 per 100,000). In California, whites living in San Francisco had a CMM incidence of 30.5 per 100,000, whereas those living in Los Angeles had an incidence of 24.9 per 100,000.
There are a few studies that suggest that chronic, low-grade exposure to sunlight may be protective against CMM. In one Austrian study, those with chronic sun exposure without sunburn had a reduced incidence of CMM compared with those with recreational sun exposure. In Germany, outdoor activities during childhood, in the absence of sunburn, were associated with a lower risk of melanoma. Chronic, repeated sun exposure may allow the skin to accommodate to UV radiation by increasing melanin production, thereby reducing the risk of sunburn. An English study published in 2011 showed that regular weekend sun exposure had a protective effect against CMM, and the researchers postulated that this may be mediated by photo-adaptation or higher vitamin D levels.
It's going to take a lot to convince me, at 56 and very aware of sun damage to the skin of my friends who spend more time in the sun than I do, that "healthy tan" isn't an oxymoron.
My dad died of malignant melanoma. He wore sun screen all the time. He didn't swim. He would wear sun hats. He was paranoid, and likely had premonition of it. Unfortunately, his prevention methods might have actually exacerbated his odds even further because he was depriving his skin of one of its few natural healing modalities.