But according to NewsTarget (or whatever-the-hell they call themselves now), and Joe Mercola, there is a conspiracy between oncologists and sunscreen manufacturers. (I’m not going to link to them this time—it gives me a rash).
The premise set forth by the quacks is that sunscreen lowers vitamin D levels, and contain toxins, both of which will lead to…um…something bad. Or at least, something worse than skin cancer, which is clearly caused by sun exposure. It has been proved beyond any reasonable doubt that sun exposure causes cancer, and that sunscreens can help prevent this…
The key word here is “reasonable”, a state that escapes the likes of Mercola and Mike Adams. Mercola even hosts an article called “Reduce your risk of cancer with sunlight exposure.” (I have to link to this one so that you can see the sun-blackened stupid yourself.)
Let me repeat the important point here—sunlight exposure causes skin cancer, and sun avoidance with the use of sunscreens helps prevent cancer. Vitamin D deficiency is common in northern latitudes, can cause weak bones, and is preventable with oral vitamin D supplements, which do not cause cancer.
According to Mercola’s pet quack:
If protection against UVR were the most important thing, all humans would have very dark skin, since the melanin in dark skin protects against skin cancer and premature skin aging.
There are several problems with the sentence. First, it may be true that evolution has favored darker skin in sunnier climes to protect against cancer, and fairer skin in northern climes, perhaps to help with vitamin D absorption, or perhaps as a simple accidental evolutionary loss of skin pigmentation. In northern climates, with less sun exposure, there is much less evolutionary pressure toward dark skin. Therefore, from an evolutionary perspective, you would not expect all people to have dark skin, any more than you would expect all humans to have a high prevalence of sickle cell genes, which protects against tropical parasites.
His premise also rests on the idea that vitamin D deficiency conveys a higher risk of cancer than sun exposure—a completely unsupported hypothesis.
He goes on to recommend sunlight as the only good source of vitamin D, even though adequate oral supplementation is cheap and easy to take. The author recommends sunlight because he feels that official recommendations for vitamin D will not catch up to what is needed any time soon. The obvious logical fallacy here is that he could just as easily recommend oral vitamin D supplementation.
Mercola actually gives his stamp of approval to UV light exposure, a known powerful carcinogen, and endorses its use. This would be considered malpractice were the advice given to an individual, rather than posted on the web.
Shame, shame, shame.
References (the legit ones)
Orac reminded me of an excellent post on the topic. It goes into the details of some of the studies cited by the quacks.
Gilchrest, B. Sunscreens—a public health opportunity. NEJM, 329(16), pp. 1193-1194. http://content.nejm.org/cgi/content/full/329/16/1193
There are other effects of a nearly transparent skin other than vitamin D synthesis. There are many photochemical reactions that involve nitric oxide. I suspect that more photochemical NO production from nitrite/nitrate in the skin may be an important factor in loss of skin pigmentation. That may be why hair turns white with age, and why male pattern baldness removes hair from the top of the head.
Male pattern baldness also has something to do with genetics and with testosterone levels.
Seems I have run across more than one study that says the opposite of what you are claiming.
http://uvtalk.com/forum/forumdisplay.php?f=8
“Mercola actually gives his stamp of approval to UV light exposure, a known powerful carcinogen, and endorses its use. This would be considered malpractice were the advice given to an individual, rather than posted on the web.”
What about the known powerful carcinogens in SPF? Oh I guess when you are just marketing scare tactics then the actual product doesn’t really matter as long as it sells.
This is just crazy.
The REAL problem is that the dermatologists are using their MDs to back their scare tactics into making people think they are real.
About 7800 people die every year in the USA from Melanoma.
7800 people…out of 300MILLION. In any other circumstance this would be written off immediately as STATISTICALLY INSIGNIFICANT cause out of 300,000,000 people that many will most likely die of Melanoma just cause. How many do you think are actually from sun exposure? 6?
Who are we protecting? Albinos? People with messed up immune systems? People who abuse their bodies?
Still, even after factoring in all of the above it’s only about 7800 a year.
In a time of war and economic hard ships do we really need to focus on this non issue?
funny, another statistic says that 50% of the USA is Vitamin D deficient. That’s 150MILLION PEOPLE. What is caused from this deficiency? How about Diabetes and Osteoporosis. That’s not a big deal?
That’s 150,000,000 people. So 150million people at risk for diabetes and osteoporosis is nothing but 7800 people is?
Come on now. These people MUST have something better to come up with than worrying about a couple thousand people. If they care so much why is it that more people die every year from a misdiagnosis from a doctor?
“Studies of autopsies have shown that doctors seriously misdiagnose fatal illnesses about 20 percent of the time. So millions of patients are being treated for the wrong disease.”
http://www.isabelhealthcare.com/info/newyorktime.html
I think we have a big problem on our hands in the form of Dermatologists that have been wrong about the dangers of the sun and realize what they maybe liable for if the truth comes out.
How can ALL SPF be good? do they even look at what’s in the bottle?
OMG, you people are friggin’ nuts. You probably shouldn’t type without engaging your brain, such as it is.
First, one “study” proves nothing. The vast preponderance of the evidence is quite clear.
Assuming your figure of 7800 people dying of melanoma yearly is correct, that is quite a tragedy. Most of those deaths were preventable.
How many internal cancers deaths could have been provented with moderate UV exposure for Vitamin D production?
Neat how skin cancers rates have gone up since the suncare coalition and sunscreen manufacturers began there war on the sun.
“suncare coalition”???
ROFLMAO!
Are you a member?
You are correct, male pattern baldness (also called androgenic alopecia in females which is in almost the same place) is mediated through testosterone. Testosterone is mediated through NO. Low NO increases testosterone synthesis because NO inhibits the cytochrome P450 enzyme that is the rate limiting step in testosterone synthesis. I suspect that a high androgen level is a generic feedback mechanism to increase NO production. One of the major symptoms of increased androgens is hirsutism. That increases hair growth and so would facilitate the growth of the bacteria that I am working with in the places where that hair growth is stimulated. I think that providing a niche for these bacteria is the major reason that humans have hair where they do. On the scalp which is thin and well vascularized and which has emissary veins draining through the skull and into the brain. Under the arms close to major arteries and lymph nodes, receiving drainage from the arms, major antigen sources being the hands. Certainly hair under the arms is not there to provide warmth. Pubic hair is to provide a reservoir of these bacteria to protect the various orifices from infection by supplying nitrite (a powerful broad-spectrum anti-microbial agent).
What is interesting is that pubic hair pretty much doesn’t turn white as fast as scalp hair does. The bacteria I am working with are sensitive to light, that may be a mechanism to protect them.
How do people this stupid get out of bed in the morning without strangling themselves with the sheet?
Card-carrying!
Obviously I have mistaken this for an intelligent debate. My apologies carry on with yourself.
“Your an idiot, babe, it’s a wonder that you still know how to breathe.”
—Bob Dylan
When you asked a silly question like “are you a member of the suncare coalition”, I, in generosity, assumed that, rather than being a raving paranoiac, you were making fun. Excuse my mistake.
BTW, @Joe, the article you linked to in the NYT is completely irrelevant. Nice work.
But perhaps I didn’t devote the time necessary to understand the above criticisms…
No. I did.
If you were to look at the link that John provided, you would find links to such research as http://www.dana-farber.org/abo/news/press/2007/guardian-of-the-genome-protein-found-to-underlie-skin-tanning.html. This study was done at Harvard’s Dana Farber Cancer Center.
What about Dr. Garland at University of California, SD and Michael Holick at Boston University School of Medicine? http://www.medicalnewstoday.com/articles/30769.php
http://www.eurekalert.org/pub_releases/2007-08/uoc–ssm082107.php
You could also check out Dr. Holick’s article in the New England Journal of Medicine on vitamin D deficiency. It is saved in a pdf here. http://uvtalk.com/forum/showthread.php?t=251
If you believe that all the information about SPF and sun exposure over the last 20 years is all accurate and unbiased, try to find any proof that moderate, non burning sun exposure is related to an increase in melanoma. In fact, recent research says just the opposite.
It is amazing that the pharmaceutical industry that manufactures sunscreens can put out that the sun will kill you if you don’t use their product and the public actually believes it without questioning.
I have to say, it never occurred to me that this post would attract a lot of, um, attention. I never knew there was a cult of sun worship out there. Apparently, they’ve stared into the object of their worship so long that they have become blind to reality.
Sad. Sort of.
The problem with UV exposure is that a single UV photon has enough energy to break a DNA strand. Whether that break causes cancer or not depends on where the break is, and whether or not the repair enzymes can fix the break fast enough and with enough fidelity. There is no UV exposure that does not cause damage. A single photon can cause damaged DNA. It is only a matter of luck if that photon hits DNA in a harmless spot or a critical spot or misses it entirely.
The repair fidelity depends in part on how many times it gets broken and fixed. It also depends on the rate at which the damage happens because repair only occurs at a certain rate, if the damage occurs faster than it can be fixed, the damage can accumulate resulting in damage that can’t be fixed.
Cancer isn’t the only problem with DNA damage. Once the DNA is permanently damaged, that cell and all daughter cells that derive from that cell can never repair it. Once damage occurs in the DNA coding for repair processes, the cell is S.O.L. The damage will only increase, and increase at an accelerating rate.
UV is not the only source of things that damage DNA. It is one source that can be controlled. What the sun screens do is slow down the rate, so the repair enzymes can do their job better.
It just struck me as ironic Daedalus is warning me against the dangers of the sun. Perhaps I should have chosen the name Icarus to post under.
I assure you that I agree, if you get too close to the sun, it will “melt your wings” and cause you harm. But, where I posted links to actual research, you posted the same rhetoric that has been “common knowledge” for the last 25 years.
There was a time that it was common knowledge that it was a waste of time for a surgeon to wash their hands between operations. That same common knowledge said that gastric ulcers were caused only by excess gastric acid, not by a H. Pylori.
If you could, please look at the most current research that says lotion manufacturers have overstated the protective benefits of SPF.
Don’t write me off as some heliophile crackpot. OR do, I don’t really have anything to lose either way.
Over the last 5 to 7 years, there has really been a leveling of the playing field in terms of information available. There are no secrets if you are willing to look for the information. I don’t know what your background is, so I hope I’m not being too simplistic. Do a google search for p53. Also, I see that Dana Farber link is broken. Search “master watchman of the genome” to find that article on DF’s website.
Google Michael Holick, Cedric Garland and William Grant. These are not Mercola type profiteers. They are respected scientists that are leading the research in vitamin D and UV exposure.
Or, sit back and be content that you know far more than I ever could. Either way, have a good night.
I love the sun. I love the way I feel after an hour of being in it’s warm rays. I always feel much happier coming home from a walk in the park or a lazy afternoon reading on the beach. I am also a firm believer that you can’t over do it and need to be smart about your exposure. Our largest organ needs to be treated with care and respect.
I also believe that the chemicals in the store brand sunscreens are much more harmful than the rays they’re supposed to protect us from. PABA, TEA, Glycerin, fragrances, propylene glycol and a whole host of other chemicals go on our skin and absorb into our blood stream and organs. We’d be better off eating the stuff. At least then our bodies would have a chance of eliminating some of their harmful toxins. What about those known carcinogens and their effects? Who’s going to tell the big businesses that make them to use safer ingredients? The Government, the insurance companies, the hospitals, drug companies, medical equipment suppliers, research institutes and a multitude of other people and businesses combine to make Cancer the biggest business in the world. We as consumers are paying for it whether we enjoy the sun or not so I say get out for a walk!
the fact that the sun makes my skin darker, similar to putting a piece of bread in the toaster makes it darker…
that’s enough to make me fear and respect the power of UV. i don’t slather myself in sun lotion – nor do i sit in the sun for hours on end. if i’m gunna be spending a week in the sun, i use lotion. the lotion does work. I don’t know why you’re referring to it as “SPF” – SPF is a ratio, not an ingredient/whatever. My cousin is a dermatologist, and she said “it’s better to use spf10 and reapply more often than to try and get away with using spf 50.
Um, UV fans?
Go to http://www.steripen.com. See the funny little device all those people are sticking in bottles of water? That’s a SteriPEN. It’s the best water purifier around, and it works using UV light. You can get a solar-charged version (http://www.thetravelinsider.info/travelaccessories/steripensolarrecharger.htm), which is great if you’re going to be off the grid for extended periods of time.
One of the things the SteriPEN’s makers emphasize is to NEVER turn the thing on UNLESS it’s actually in water. That’s because of its output of UV rays; it’s safe to run in water because even an inch of water is a sufficient UV barrier, but never, ever pull it out of the bottle while it’s still running. That is because the same UV rays that so effectively kill off the crud in your water are inimical to you as well; UV is no respecter of organic cellular structure.
Oh, and speaking as someone with fair skin, bazillions of moles, and a family history in which skin cancer does not run but gallops, I’ll be ladling on the SPF 50 from April to October anytime I’m out in the sun for more than fifteen minutes at a time.
To say that say that melanogenesis is similar the the oxidation that takes place by toasting bread is, well, let’s just be kind and say it is inaccurate.
My reference to SPF, while technically inaccurate, is common and refers to the chemicals in sunscreens that block UVB. Some of the newer sunscreens have started blocking some UVA as well.
A steripen produces UVC, similar to an arc welder. Not anything like the UV exposure you get from either natural sunlight or from artificially produced UV from tanning lamps.
Finally, SPF 8 blocks over 80% of the vitamin D production in the body.
I noticed on another thread in this blog a list of suggested question to ask your doctor. I predict that it will be soon you will need to add, “What is my serum level of vitamin D?”
I am not trying to be argumentative. I hope it isn’t coming across that way. I have been following this research for a couple of years now. The more you look, the more it appears (to me) that UV exposure is like most things in life. Moderation is the key. Moderate UV exposure stimulates P53 production and actually appears to help fight DNA damage and tumor production. P53 is important in regulating apoptosis.
p53 is a bit more complex than you think.
Anyway, vitamin D is quite important, and its role is becoming better and better understood. But in deficiency states, we have safe and effective ways to replace it, rather then stimulating it’s hydroxylation with a known carcinogen. Vit D2 and D3 are widely available.
daedalus2u said, “What is interesting is that pubic hair pretty much doesn’t turn white as fast as scalp hair does. The bacteria I am working with are sensitive to light, that may be a mechanism to protect them.”
Your bacteria have pubic hair?!
andrea
What would you know; you’re only an entomologist!