Here’s something unexpected: Sunbathers live longer

Robert H. Shmerling, MD
Robert H. Shmerling, MD, Faculty Editor, Harvard Health Publications

Surprising, right? But that’s the conclusion of a new study that compared the life spans of many people with varying amounts of sun exposure. They found that among nearly 30,000 women in Sweden, who were each monitored for about 20 years, those who spent more time in the sun actually lived longer and had less heart disease and fewer non-cancer deaths than those who reported less sun exposure.

Can the sun extend your life?

With summer just around the corner, this news is timely — and a great excuse to get out of the house or office and soak up some sun. But there are some important caveats about this research:

  • Deaths due to cancer were more common among those who spent more time in the sun (The authors suggest that the higher probability of being diagnosed with cancer among the sun worshippers was because they were surviving longer and not dying as often of other causes)
  • The impact of sun exposure on longevity was relatively small. Even those with the greatest sun exposure only benefited from an extra 7 months to 2 years of life.
  • This study detected an association between sun exposure and a lower frequency of certain causes of death; however, that’s not the same as proving that sun exposure was the cause of longer life. It could turn out that there is another explanation for these results that has little to do with sun exposure itself. For example, perhaps people with more sun exposure tend to be more active, smoke less, and have healthier diets. The researchers tried to account for other factors such as these in their analysis, but it’s always possible that something important was overlooked.
  • The reason why more sun exposure might prolong life or prevent heart disease deaths could not be determined by this study. Because the sun’s UV light triggers chemical reactions in the skin that lead to the production of vitamin D, it’s possible that vitamin D is responsible for the health benefits of sun exposure described in this study. And that could mean vitamin D supplements would promote longer life free of heart disease, even without sun exposure. However, that’s only speculation and prior studies have not been able to prove this.
  • The study did not include men. The impact of sun exposure could be quite different among men.

Before you ditch the sunscreen and head for the beach…

While there is some uncertainty about the overall importance of this study, one thing is for sure: when it comes to the impact of sun exposure on health and disease, the findings of this new report won’t be the last word. There are competing risks linked to sun exposure: skin cancer and other skin damage are clearly a risk; but there may be health benefits as well (as suggested by this study). Since this type of study cannot determine the exact reason that those with more sun exposure lived longer, we’ll need more research to sort out just how much sun exposure is best.

The authors of this study speculate that recommendations to limit sun exposure might actually do more harm than good; in fact, they suggest that avoiding the sun could have a negative health impact similar in magnitude to smoking. That’s quite a statement!

In my opinion, that kind of declaration is premature and overstates what we can conclude from this type of research. After all, there are plenty of examples in which retrospective studies like this one (that is, those that ask people to think back and self-report their experiences with an exposure or treatment) turned out to be completely wrong. Routine hormone replacement therapy for perimenopausal women is one of the most dramatic and recent examples. Let’s not make sun exposure the next one.

Related Information: A Plan for Successful Aging

Comments:

  1. Bruce Tizes, MD, Medical Editor, http://www.medicalcitizen.com

    My guess is that use of UVA and UVB blockers, motivated largely by a desire to decrease skin cancer risk, traded relatively easily curable skin cancers for incurable and/or more advanced bowel, breast, thyroid and other tumors… an unexpected and unhappy consequence.

  2. Zoey141

    Insightful write up… But then, I have my doubt about sun bathing being beneficial for all. I’ve been battling psoriasis for over a decade now, and exposing my skin to sunlight has always proved to be a bad idea. I do take risk sometimes, but it hasn’t really paid off. Although researchers are all for sun bathing, I personally think people with psoriasis should avoid it. Better be safe than sorry, right>?

  3. Sara Keylor

    If you spend alot of time outside, you most likely are working, farming, fishing,and other noble activities…therefore better health. There are way too many variables that make this study literally Swiss Cheese!

  4. Maria Jasmine Freeman

    Sunlight exposure decreases depression incidence, and depression is a risk factor for unhealthy living, thus higher death risk. More, as mentioned, vutaminD resulting from sunexposure, has multiple benefits. Additionally, to start with, those who spent more time in the sun could have commenced with better life circumstances, less stress, healthier environment and food, and more supportive family life, etc…
    It has to be kept in mind though, that with a hole in the ozone gap-albeit recently ameliorated, sun exposure nowadays is more risky as to skin cancer-and more, than many years ago, so a sun -exposure strategy has to be adopted with caution, especially in the greater-risk group!
    Dr Hana Fayyad

  5. Joan Ravenna

    consider this: sunbathing is a ritual. a relaxation and often social activity or athletic activity.
    All those factors are life enriching, possibly prolonging and hopefully enjoyable.
    What makes life better may be what makes it longer.
    There are studies about saunas lengthening life for heart patients. Just the opposite of conventional advice. Question the conventional advice!
    Joan Ravenna

  6. Manny

    Good article but take the time to read the whole journal study done in Sweden using about 29,000 participants.
    My advice after working on this issue with the FDA for 22 years and attending the National Council of Skin Cancer Prevention meeting for 5 years is to use a contingency approach depending on your skin type. The lighter your skin color the more precautions that you need to take from getting sun burned and other skin cancer risks..
    However other studies have show also that folks with with non melanoma skin cancer actually live longer than most people.. For me sunlight helps with my psoriasis. I also use Talconex for it and use a tanning bed in the winter months when my psoriasis is really a problem. Everything in moderation and follow your doctors advice…

  7. gretta gribble

    heavier people are more likely to have risks for earlier death and are also less likely to go out in scanty swimwear. was weight – waist circumference, bmi, etc – considered?

  8. Melissa Kazantzis

    Hi editor

    In the sentence ” Since this type of study cannot determine the exact reason that sun avoiders lived longer, we’ll need more research to sort out just how much sun exposure is best.”

    I believe the word avoiders was intended to mean “bathers” ?

    Thanks for this great publication!

  9. Renee3

    Everything in moderation. Of course if you bake and burn in the sun, that wouldn’t be wise, but completely avoiding the sun can’t be good for your health either. There are many benefits to getting some sun. I live in NY and it is difficult to keep my vitamin D level up. Many doctors think supplementing doesn’t offer the same benefits.

  10. steve

    I would expect those more in the sun would drink more alcohol. The author seems to be bent on taking away the benefits of sun exposure and attributing its health benefits to other things.

  11. Carol Glasscock

    Ridiculous and dangerous column! Let’s just ask my husband, who has had repeated serious skin cancer surgery from sun exposure as a teenager. It has almost killed him twice. And the radiation from skin cancer treatment has damaged his heart. He is currently very ill with heart failure.
    It makes me sick that someone would twist and skew unreliable results to come to a wrong conclusion. Thanks to this column, many people who live here in Pensacola, Florida will head to the beach thinking “Whew! So glad that danger is over.”
    Shame on you!

  12. Dr. K S Parthasarathy

    This “study” has red flags at many points. It will be interesting to speculate a mechanism for the apparent longevity of sunbathers.
    The juicy title “Sunbathers live longer” became more realistic as the text advanced.
    The usual caveat “Comments on this blog do not represent the views of our editors or Harvard University, and have not been checked for accuracy.” may save the reputation of Harvard University.

    In spite of ther caveat , Harvard University wants ” All comments submitted to this site become the non-exclusive property of Harvard University.”

    • Manny

      Hello
      was part of FDA effort to review the Swedish Study in 1992 indicating that sunbed usage increase risk of CMM. The correlation was only suggestive.. Both Dr Cyr and Dr Beer felt that it was the early sun burns that contributed to CMM. Spent five years representing FDA at National council of Skin Cancer Prevention meeting.. There has been some peer reviewed research that show that folks with NMSC actually live longer..The benefits and risks associated with uv light exposure needs further study . There are so many confounding factors.. The lighter skinned folks are at higher risk for sun burn but benefit from shorter exposures from a UVB vitamin D 3 perspective. All a skin type 2 needs is about 100 JM2 of UVB to get their dose of vitamin D 3 and they get a minimal Erythemal does at about 156 JM2…
      Biotin line each person skin type is different and the lighter the skin the more burn or cancer risk and more vitamin d3 benefit. The opposite is true for Afro Americans less cancer risk and less benefit from vitamin d 3. A hormone that is very important to human health.. Could this be a contributing factor to increased cancer rates in the Afro American community.. ???
      of vit

  13. Mike Lipsky

    Sun tanning is a natural and intended process of the body with beautiful benefits When practicing moderation. The correct spirit of some care should be educating people to minimize the risk of overexposure, or sunburn, while still allowing them to enjoy a regular exposure to the sun.

    • Manny Karos Allied Quality Services LLC

      Good point Mike
      I enjoy reading your colums in IST.
      I hope the Brits don’t break away..

      Met a bunch of them on a cruise out Venice last month..
      A lot of them on the pool deck:)

  14. gretta gribble

    no comment on the role of weight, waist circumference, etc. heavier people have more health risks, but are less likely to go out in bathing suits. (some do, of course.)

  15. Vince

    You know the evidence that sun avoidance and sun screen prolongs life is far less convincing than the study above. Yet that lack of evidence has not stopped M.Ds from encouraging sun avoidance and sunscreens even as this study suggest it shortens you life. Sun screens have never been shown to prevent melanoma to my knowledge yet that is the belief system. The bias is clearly shown by the statement that up to a 2 year longer life span is ‘small ‘ somehow I think that if a really toxic Chemo loaded with side effects extended life in some it would be considered “HUGE’ be .Belief is not evidence. I few of the less than proven statements in this thread. Melanoma is usually caused by sun exposure. all quotes from “And the link between melanoma and sun exposure is not straightforward. Dr. Marianne Berwick, an epidemiologist at the University of New Mexico who studies skin cancer, led a study published in The Journal of the National Cancer Institute in 2005 finding that people who had a lot of sun exposure up to the time they got a diagnosis of melanoma actually had better survival rates than those who had little sun exposure. ……” Sunscreens save lives ‘….”“It’s just not that simple,” said Dr. Barry Kramer, associate director for disease prevention at the National Institutes of Health.
    Continue reading the main story

    “We do have some pretty good evidence that sunscreen will reduce your risk of the less lethal forms of skin cancer,” Dr. Kramer added. “There’s very little evidence that sunscreens protect you against melanoma, yet you often hear that as the dominant message.” The times piece is a good read

  16. Alaa abdelmoniem mohamed

    I believe, exposure to the sun rays would be limited on the periods that not effected the skin. Is that correct?

  17. Con Tan

    of the uv rays, only uv B is effective in promoting vitamin D synthesis on skin. The amount of uv B is governed by the azimuth of the sun. In New Zealand, between end of March and early September, UV B B is hardly present in the sun. Even for those months when UV B is present, the effective durations could be half an hour or less around noon.

  18. karen mundy

    Another theory on sun exposure and longevity. Sweden is an affluent country, with very few low level jobs.

    Perhaps the sun devotees were high SES (socio-economic status), having the leisure time to be in the sun. So the real independent variable would be SES, a marker for well-being in a variety of areas.

  19. 1Ronald

    Unexpected? We’ve known this for years. My lifeguard died last year at age 95. In the sun, by the ocean, all day every day. Now, the people wanting to sell you that cancer causing sunscreen don’t want you to know this.

    • Ridley

      Cancer CAUSING sunscreen?

      • jk

        Yes cancer causing sunscreen. Back in the early days of chemical laced body care products, the hair and body care products industry along with the chemical companies noticed the correlation between the use of their products and the rise in cancer rates. So what they did was conspire to blame the skin cancer on the sun. Remember PABA and sunscreen? The spike was covered up and the incidence of skin cancers has continued to rise.

        As the rates of skin cancer increased, it became news. And the makers of tanning lotions saw an opportunity. They repositioned their products as “sunscreen.” After that, the sales of sunscreen continued to climb… along with the rates of melanoma.1 In fact, the per capita melanoma rate has increased 1,800 percent since the first commercial sunscreens were introduced.

      • Henry

        Come on – “cancer-causing” was surely what he meant.

      • JY

        Many chemicals used in sunscreen increase ROS. The experts tell us that the sun causes ROS, and this is why we need protection from sunscreen. Therefore many chemicals used in sunscreen may actually exacerbate the problems associated with sun exposure, especially if not enough sunscreen is used or not reapplied frequently enough. If you are interested in this subject, read up on the need for Toxic Substance Control reform.

    • kingdomarc

      i guess still people dont get it. vegetables, algae, etc spend all day in the sun and dont burn, instead they get these protective compounds that when we eat these foods we can get to protect ourselves from the sun. it is because we are so unhealthy that we get photo damage, not because the sun is bad. it doesnt mean we have to spend hours in the sun and toast, common sense is key. something else that will protect you from the sun is good fats, but they have demonized those too. Again we are so sick our bodies cant handle anything because we have been brainwashed that good is bad and bad is good.

  20. Rich

    Association versus correlation is one of the most fundamental of research principles. There are over 5 million skin cancers diagnosed each year. Melanoma accounts for over 75,000 cases of new skin cancer. Each year. Melanoma is deadly if not treated early, and it is usually caused by sun exposure. Who reviews these articles before you send them out? Could you not take a break from selling publications for a tiny moment to put the caveat more upfront?

    • Joe Ciccone

      and how many people die from this ?
      The sale and use of sunscreens seems to rise along with the increased incidences of skin cancer.
      The are certainly other factors besides the sun, causing these increases.

      • lola joaquin

        That’s because some sunscreens contain carcinogenic ingredients!
        Check you sunscreen against the list tested and published by EWG (Environmental Working Group)

  21. Robert Diffin MD

    Personally, I found your comment wanting that the “sun advantage” is relatively small (7-24 months) as more valid when speaking of a 3, 9. or 15 year old. It is more important to a 40 or 50 year old.
    Secondly, you had a prime opportunity to educate your audience as to the “ideal” time of the day and time of exposure if a person desires to gain the benefit of the sun, and minimize potential harm.

  22. Josephine

    What to believe: a) sun is bad for you skin=you can develop skin cancer (melanomas etc) .
    And now: sunbath is good, extends your life.
    ??????????

  23. Patricia Hickerson

    Humans lived outside for most of the day until recently. As I understand it, the form of vitamin D formed from exposure to sunlight is a hormone. Hormones interact with other hormones and our biorhythms. Most of my ancestors were in northern Europe. I live near 38 degrees north in the U.S. If I’m in the sun midday, I sunburn in 5 minutes. Still, I try to get some sun exposure every day. It always makes me feel better and sleep better.

  24. Taleena

    I too feel this was an “Enquirer” type headline. Harvard should be ashamed of themselves for using such a misleading headline in what should be a medical article.

    • Joe Ciccone

      Harvard is just selling information that if you search you might find without spending $20 bucks…..
      their not going to print this comment…..that’s become the American way…

  25. Sami Sozuer

    Sweden is way up north! On a yearly basis, it gets much less sunlight
    than more southern parts of the world such as the US. Considering that we evolved from ancestors from Africa, it may just be that people
    in Sweden normally get much less than “normal” sun exposure. But
    as for me who lives around 40th latitude, I believe I get more sun exposure than the person with the highest sun exposure in the study.

    What about conducting a similar study in southern Italy? That could shed some light on the apparent paradox we face.

    • Noah Freedman

      Excellent point. Dr. Bruce Hollis has a lot of data on how, even at latitude 40 degrees , it is hard to make any vitamin D from sunlight at all between the months of November and March, and then it is only possible between the hours of 10 am and 2 pm standard time. Though, since I am sitting up here at 6600 ft above sea-level, whether a thinner atmosphere has greater risk of UV exposure as others have told me.

      • sami sozuer

        UV exposure certainly increases with altitude. I once climbed a 3500m mountain and I got serious sunburn in spite of the sunscreen I was wearing.

        WHO’s webpage says UV exposure increases by 10-12 % with every 1000m increase in altitude. So compared to sea level your UV exposure would be 20-25 % higher at 6600ft.

    • Noah Freedman

      Excellent point. Dr. Bruce Hollis has a lot of data on how, even at latitude 40 degrees , it is hard to make any vitamin D from sunlight at all between the months of November and March, and then it is only possible to make vitamin D between March and November between the hours of 10 am and 2 pm standard time. Though, since I am sitting up here at 6600 ft above sea-level, I wonder whether a thinner atmosphere has greater risk of UV exposure, as others have told me.

  26. Gerald Dassler

    The E mailed intro to this Blog was VERY misleading.

    I would expect a scientific approach from Harvard Medical – not what felt to me like a National Enquirer lead in.

  27. Nancy Doherty

    The study was in Sweden, a very northern country with long, dark winters. Just how much sun exposure were the women getting, especially compared to women at lower latitudes?

  28. deforddennis

    Perhaps the reason is that people who spend more time outside are more social.

  29. Rita Brock

    I suggest it might be because sun exposure aids in more restorative, deeper, and longer sleep. Sleep deprivation is tied to all kinds of ill health susceptibilities like type 2 diabetes, loss of memory, risk of heart disease, and impaired immune functions. Our diurnal clocks fail to reset for good sleep if our retinas are not exposed to an hour of sunlight midday, every day. I’ve found all day exposure assures a good night’s sleep, even when crossing multiple time zones with no jet lag if I am outdoors all day for a couple of days.