Study shines light on the fact that sunscreens don’t appear to offer real protection against melanoma

It’s usually this time of year where we see a rash of stories in the press warning us of the dire perils of sunlight and the ‘essential’ nature of sunscreens in protection from it. This year was a bit different, though, in that I don’t think we’ve anything like the usual number of sun scare reports. Plus, this week, we saw in the UK considerable interest in a study that cast doubts about the ability of sunscreens to protect against malignant melanoma (generally, the most serious form of skin cancer).

The study was done in mice [1], and you can read a report about it on the BBC website here. The bottom line is that this study found that factor 50 sunscreen increased the time it took for light exposure to induce melanoma, but the melanoma developed all the same. The take-away message from the study has been ‘don’t rely on sunscreens, use other means to protect yourself from sunlight such as seeking shade and wearing appropriate clothing’.

We cannot always extrapolate the findings of animal studies to humans. However, taking the study at face value and assuming it does apply to us, should we be too surprised by the findings? Actually, no: while sunscreens can help us extend our time in the sun without burning, there is evidence that relying on them for the prevention of skin cancer may be misguided.

In 2000, the International Agency for Research on Cancer in France held a meeting to discuss the role of sunscreens in skin cancer prevention. A report of the meeting’s findings was subsequently published [1]. The Agency concluded that there was evidence that sunscreens could reduce the risk of squamous cell cancer (one of the three main types of skin cancer) but only if individuals did not use sunscreens to extend their time in the sun. Actually, a lot of people use sunscreens in just this way. When people coat themselves in sunscreen on the beach or by the pool, the usual intention is to allow them to stay longer in the sun without burning.

But what of the role of sunscreens in melanoma prevention? A press release generated from the meeting stated that:

Several relevant epidemiological studies have shown significantly higher risks for melanoma in users of sunscreens than in non-users. This paradoxical observation could in part be due to the fact that users of sunscreens deliberately spend more time in the sun than they would otherwise. Thus, the protective effect of sunscreens can be outweighed by overexposure based on the false assumption that sunscreens completely abolish the adverse the adverse effects of [ultraviolet] light. In light of these findings, [we] concluded that sunscreens prevent sunburns and may reduce the risk of squamous cell carcinoma, but only if they do not mislead people to extend their exposure to sunlight.

In another review of the role of sunscreens in skin cancer prevention it was concluded that:

…no melanoma study has shown convincingly that sunscreen use reduces the risk of melanoma [2].

The authors forward several theories for why this might be, including the fact that sunscreens may protect against burning by blocking ultraviolet B (UVB) rays but may allow longer exposure to potentially damaging rays from other parts of the spectrum (such as UVA). The vitamin D-blocking effects of sunscreens is also cited, along with the potentially carcinogenic nature of certain chemicals used in sunscreens including avobenzone and ecamsule.

The article goes on to refer to the fact that:

…interests that are not scientifically based seem to be driving the heavy reliance on sunscreens as the first line of prevention against skin cancer”…“The fervor with which companies promote sunscreen can perhaps be traced to the profit that sunscreen sales bring.

Further cause for concern comes from a research linking sunscreen use with not just malignant melanoma, but basal cell carcinoma [the third main type of skin cancer] too [3].

Personally, I don’t advocate the widespread use of sunscreens, and have not used them myself for more than 20 years.

While I’m no fan of sunscreens, sunburn is still something that should be avoided if at all possible. My advice here is to employ physical (rather than chemical) protection. I am delighted that this most recent research [1] has meant more focus is being placed on this strategy.

Around water it’s especially important to protect the skin when the sun is baking hot. The use of specialised clothing for wearing in water is a very good idea, here, I think. Being in water is one situation where there is an argument for sunscreen on parts of the body that are at risk of burning that cannot be protected with clothing, such as the face and ears.

References:

1.    Viros A, et al. Ultraviolet radiation accelerates BRAF-driven melanomagenesis by targeting TP53. Nature published on-line 11 June 2014

2.    Vainio H, et al. Cancer-preventive effects of sunscreens are uncertain. Scandinavian Journal of Work and Environmental Health 2000;26(6):529-531

3.    Berwick M. The good, the bad and the ugly of sunscreens. Clinical Pharmacology and Therapeutics 2011;89(1):31-33

4.    Autier P. Sunscreen abuse for intentional sun exposure. Br J Dermatol 2009;161 Suppl 3:40-5

11 Responses to Study shines light on the fact that sunscreens don’t appear to offer real protection against melanoma

  1. PhilT 13 June 2014 at 7:47 am #

    Sunscreen seems to be suffering from inflation too – everything seems to be factor 15 or higher, you have to hunt around to find sensible factors like 4 or 8 that allow me to spend several hours in the sun with the equivalent of less than 1 hours UV exposure.

  2. Thomas Murphy 13 June 2014 at 8:32 am #

    Not necessarily for publication!

    Quote:

    The study was done in mice [1], and you can read a report about it on the BBC website here. The bottom line is that this study found that factor 50 sunscreen reduced the time it took for light exposure to induce melanoma, but the melanoma developed all the same.

    Surely this should read:

    The study was done in mice [1], and you can read a report about it on the BBC website here. The bottom line is that this study found that factor 50 sunscreen INCREASED the time it took for light exposure to induce melanoma, but the melanoma developed all the same.

    Otherwise, the statement does not make sense!

  3. Soul 13 June 2014 at 1:09 pm #

    I spent a portion of winter in sunny Florida. While there I practiced sensible sun exposure, avoiding being burnt. Occasionally I enjoying brief sun exposure to make vitamin D and other substances that UV light is reported to create in the skin. Short duration sun exposure tends to make me feel more upbeat and healthier.

    When wanting to avoid the sun I’ve found it more helpful at covering up with clothing and a hat. It’s been awhile since I’ve used sun lotions myself. For what ever reason I’ve tended to find sunscreens make me feel run down.

    There were a couple times this winter though where I found myself in the sun longer than expected and not covered up as hoped. During those times I found myself the next day with a slight burn. I found it remarkable that what helped deaden the pain best was applying simple structured water. Pretty much instantly the pain would go away and the redness would be gone quickly too.

  4. Soul 13 June 2014 at 1:34 pm #

    Not that anyone would purchase the water, just to clarify since I’ve seen there are many different types of structured water for sale. I would spray the reddened skin area with product called Willards Water, which is reported to be structured water. There are many other products sold as being similar. Don’t know if the other products are as helpful as I found this product with slight sunburns.

  5. OldTech 13 June 2014 at 6:39 pm #

    I still remember my father telling me to wear a hat and long sleeve shirts when working outdoors. He explained that was traditional method of getting protection from the sun. Of course that was in the 60′s and we knew better.

    I now follow his advice and have been since I was in my 40′s. I do have sun damage on my hands so now I also wear gloves when working outside in bright sunshine. And I will be telling my grandchildren to cover up.

    I have often wondered about how such traditions developed. Perhaps it was just preventing sunburn. When my dad was growing up on a farm it was not uncommon to be working outside in the fields all day long.

  6. Chris 13 June 2014 at 11:29 pm #

    OldTech, do you mind my asking what do you class as sun damage on your hands, and how might you describe what it looks like?

    You may be correct about cause, but it may also be easy to have ruled out other possible causes that hadn’t come to mind. For example, I’ve noted people give accounts of liver spots fading, when they give up on marg and veg oils and eat more natural fats.

  7. Mark Sanders 16 June 2014 at 6:42 pm #

    I’m curious as to why everyone thinks that sun exposure is the only cause of skin cancer. Other organs in the body obviously are not exposed to the sun and are perfectly capable of developing cancer due to other reasons.

  8. Liz Smith 17 June 2014 at 11:44 am #

    While in Australia during Dec-Feb 2014 when the temps were up to 42oc in WA. My sisters grandchildren were usually plastered in sunscreen but they all came out in red rashes so they hated putting anything on their skin. This lack of cover made them stay out of the sun which in young kids meant no going out.

    We ventured to a good pharmacy and asked if they had any sun screen without the ‘nasties’ in it, and I was taken to the area where I had a choice of about eight. Using a muscle test with all the kids I found a cream that said they could use it. The shock of the price would have choked a horse it was so expensive, A$30 = £16.50 per tube.

    It was successful in that the kids did not get the rashes and they tanned beautifully during the time of their trips to their swimming lessons.

  9. Kathy from Maine 20 June 2014 at 7:51 pm #

    You said, “Around water it’s especially important to protect the skin when the sun is baking hot.” I have an interesting story on that.

    For all my life I would burn easily and not tan well at all. That is, until one summer around 2003 when we vacationed in Key West. My husband and I chartered a boat for a day of deep-sea fishing. I brought everything I thought we would need in a big satchel, except I forgot the sunscreen! Oh well, I figured if I burned, I burned, and just decided to have fun. I wore a bathing suit with shorts on over it, and just a ball cap on my head, so I had LOTS of exposed skin.

    We were on the water most of the day, and when we got back, I was surprised that just the tops of my shoulders were only slightly pink, and even that was gone by the next day. No burn!

    Ever since then, I rarely burn (only if I’m out for like 4 hours early in the summer before I have a base tan) and I tan easily and darkly. Every weekend I mow 5 acres of grass, which takes around 3 – 4 hours. I never burn anymore and I don’t use sunscreen.

    I wouldn’t advocate this for others to try, but something sure changed for me that summer.

    I’ve always suspected there was something in the sunscreens themselves that was causing (or allowing for) the melanomas. After all, the rise in melanomas coincides with the rise in the use of sunscreens. You don’t see people like construction workers–who are out in the sun all day long–get skin cancers. It’s the lily-white folks who spend 12 hours a day in the sun for 2 weeks straight during their once-a-year vacation who get it.

  10. Ben - Bristol 1 July 2014 at 4:30 pm #

    When I think about sun screen and skin cancer and how ‘dangerous’ the sun is I can’t help feeling that it does not make sense. Even if the sun is stronger now due to the Ozone layer being thinner, does it really make sense that the SUN, the giver of all life and energy on Earth, would give us cancer?
    I am sure that our hunter gatherer ancestors did not get skin cancer. They probably stayed in the shade at midday and chilled out, but they also were exposed to a lot of extended sunlight. Surely it is what we eat that makes us susceptible to skin cancer? Skin cancer mostly is a western illness, in my opinion caused by a western junk food diet. If you eat rubbish, chemical laden foods then those same chemicals will end up in your skin, in your fat cells just below the skin and in the blood that nourishes and supplies your skin.
    Eat a clean, natural diet with lots of water and rich in antioxidants and ditch the suncream.

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