I wasn’t totally aware of the power of the sun until I was 24 years old. That was the year I shaved my comb-over and committed myself to full Michael Jordan-level baldness. You don’t realize how much sun your hair keeps off your scalp until you’re bald. It gave me an appreciation for what ants feel when they see a kid with a magnifying glass.
A few years after I shaved my head, I went to the doctor for a routine checkup. She warned me, “You should not leave the house without sunscreen, even if you are going to your car. You’ll get radiated.” She then made a zapping sound in case I missed her subtle use of the word "radiated." I heeded her advice, and I wore a hat and slathered sunscreen on my arms every day.
For a while.
Then I stopped.
I stopped when I started reading about the health benefits of vitamin D. I got interested in health in my early 30s, which apparently, a lot of guys do. I learned that vitamins were something I should put inside my body intentionally. Vitamin D is an important one, and the most efficient way to get vitamin D, I learned, was from the sun.
So now I only use sunscreen when I am outside for long periods of time. Have I made the right choice? Is this healthy? Am I getting enough vitamin D?
Or do I run the risk of exploding while walking to my car?
It’s Not You, Sun, It’s Me
Human beings evolved to adapt to their environments, and they did so in the sun. As a result, our bodies grew acclimated to being outside. So, how come some people get skin cancer and some are vitamin D deficient?
Penn State anthropology professor Nina Jablonski says it’s because human beings are globally mobile -- and the adaptation mentioned above, was specific to our true original environments. The farther we move from our ancestral homelands, the more at risk we are of losing the adaptations that once gave us an evolutionary advantage.
About two million years ago, melanin evolved in humans to regulate the body's reaction to ultraviolet rays. Pigment allowed enough ultraviolet radiation in the body to produce vitamin D, and humans became solar powered. Melanin also protected the skin from intense UV radiation. When humans migrated from the equator to places like England and Russia, they lost pigmentation.
Enter the wheel, the gasoline engine and the jet plane. Now humans of varying pigmentations live and vacation all over the globe. They also mostly live in cities, where their exposure to the sun is limited, and their ability to make vitamin D is reduced. Jablonski’s research points out that health problems compound when people do not receive enough sun or when there is a mismatch between their pigmentation and ultraviolet radiation.
If your skin is dark, Jablonski says, you have more melanin pigment than if your skin is light. This means that some of your ancestors evolved in a sunny place with high levels of UVR and that you have some built-in natural sunscreen. If your skin is light, this means some of your ancestors evolved under lower levels of UVR and that your skin is more sensitive to strong sunlight. By observing your own skin, you can learn a lot about the solar conditions under which your ancestors evolved.
Jablonski urges people to consider their geography and lifestyle when making choices about their health. Is there strong year-round sunshine? Is more time spent outdoors or indoors?
“By assessing these simple parameters of your own life, you can figure out if your skin color is matched well to your location and lifestyle or if there is some level of mismatch,” Jablonski explains. “Most people these days must compensate in some way for the mismatch between their skin and their location and/or lifestyle.”
For people with darker skin who live in places with weak sunlight and who work indoors, this means that they should compensate for a lack of vitamin D production by making sure they get adequate D through supplements, says Jablonski.
Diet alone isn’t an option when it comes to getting enough vitamin D.
For people with lighter skin living in places with strong sunlight, compensating for a mismatch between pigmentation and location means wearing sunscreen, clothing and other forms of sun protection to protect against the harmful effects of UVR.
“Like the other inhabitants of Earth, we evolved under the sun, and we are basically well adapted to sunshine,” says Jablonski. “The problems we have with the sun today that result in our getting too little or too much sunlight are of our own making and are mostly due to modern lifestyles, and to the fact that we live so much longer than most of our ancestors. When we understand and appreciate this, we can make appropriate compensation through our behavior and culture.”
- Human beings evolved to adapt to their environments, and they did so in the sun.
- Is more time spent outdoors or indoors?
- “ Diet alone isn’t an option when it comes to getting enough vitamin D. For people with lighter skin living in places with strong sunlight, compensating for a mismatch between pigmentation and location means wearing sunscreen, clothing and other forms of sun protection to protect against the harmful effects of UVR.
Fear the Sun
What is Sunburn?
Like Lichtenfeld, more than 3.5 million Americans are diagnosed annually with skin cancer. Skin cancer makes up roughly half of all cancers diagnosed in the country. If that number seems high, remember that skin is the largest organ in the human body, and it performs a wide variety of important functions, which include, for example, keeping your guts from falling out all over the floor.include:
- If that number seems high
- remember that skin is the largest organ in the human body,
- it performs a wide variety of important functions
- which include
- for example
- keeping your guts from falling out all over the floor
Our Friend, The Sun
Yet the sun confers many health benefits. A 2008 report published by Nathaniel M. Mead says that excessive UVR exposure accounts for only .1 percent of the total global burden of disease, according to the 2006 World Health Organization report “The Global Burden of Disease Due to Ultraviolet Radiation.”
Mead’s study notes that many diseases linked to excessive UVR exposure are relatively benign — apart from malignant melanoma — and occur in older age groups because of the lag between exposure and manifestation or the requirement of cumulative exposure. Skin cancer is common, but not often fatal. The same 2006 WHO report points out that a larger annual disease burden might result from inadequate UVR exposure.
You can see how this poses a conundrum for the medical community. It’s possible that people are staying out of the sun to avoid skin cancer, which is largely non-fatal, and are putting themselves at risk of much more fatal cancers and diseases as a result.
“If you do a risk-benefit analysis, sunlight increases the risk of skin cancer but reduces the risk of cancers that kill Americans,” said Dr. John Cannell, executive director of the Vitamin D Council. “Sunlight is very beneficial.”
Sunlight also lends benefits beyond vitamin D production. It has been shown to aid sleep, curb depression and possibly more. Researchers at the University of Edinburgh recently found that sun exposure may help reduce blood pressure. It’s a small study, but if its results hold up over time, it could lead more experts to conclude that a reduction in blood pressure is more beneficial to the population than the danger of non-melanoma skin cancer.
- Yet the sun confers many health benefits.
- Mead’s study notes that many diseases linked to excessive UVR exposure are relatively benign — apart from malignant melanoma — and occur in older age groups because of the lag between exposure and manifestation or the requirement of cumulative exposure.
Sun & Supplements
Flight attendants have higher cancer rates, and this doctor thinks he knows why
I did not know this before I interviewed him, but I follow a plan similar to what Cannell recommends, which is a combination of safe sun and supplements. So far it’s worked for me.
When the whole body is exposed to direct sun for brief periods, it produces vitamin D quickly, about 1,000 units per minute. The Vitamin D Council recommends 5,000 to 10,000 units per day. (You can read more about its sun recommendations and the recommendations from the American Cancer Society in the links below this story.)
Americans who live south of Atlanta are able to take advantage of good direct sun year-round. Above Atlanta, during what Cannell calls Vitamin D Winter, Americans should take vitamin D supplements because there is not enough sun or vitamin D in the diet to meet the body’s needs. I encourage you to check in with you doctor and see what they recommend for you.
Remember, everyone’s body is different, and your body is also affected by where you live geographically. So be smart. And, if you read a story one day about a guy who exploded in his driveway — my bad.
- I did not know this before I interviewed him, but I follow a plan similar to what Cannell recommends, which is a combination of safe sun and supplements.
What is Sunburn?
Flight attendants have higher cancer rates, and this doctor thinks he knows why
How to Stop Dark Skin From Tanning
How to Protect Skin in the Sun Without Sunscreen
Songs for Kids About Sun Safety
How Hot Does it Have to Be Outside to Get a Tan?
Dark Pigmentation Around My Mouth
Vitamin D & Excessive Sweating
How to Stop Skin From Getting Darker From the Sun
Lack of What Vitamin Leads to Brown Spots on Hands
- Pearce, SHS, and Cheetham, TD. BMJ. 2010; 340:142-147.
- Pfotenhauer, KM, and Shubrook, JH. Vitamin D Deficiency, Its Role in Health and Disease, and Current Supplementation Recommendations. The Journal of the American Osteopathic Association. 2017; 117(5):301-305.
- Sunscreen. PubMed Health. www.ncbi.nlm.nih.gov.
- Vitamin D: Fact Sheet for Health Professionals. NIH. www.nih.gov.
- Modern life may cause sun exposure, skin pigmentation mismatch
- Cancer Facts and Figures 2013
- Benefits of Sunlight: A Bright Spot for Human Health
- Study: Benefits of sun exposure may outweigh risks
- How do I get the vitamin D my body needs?
- Be Safe in the Sun
- Solar ultraviolet radiation: Global burden of disease from solar ultraviolet radiation
Joe Donatelli is a journalist in Los Angeles and the publisher of the Humor Columnist website. His work has appeared in Salon, Cracked.com, DAME and other publications. Donatelli is a graduate of Ohio University's E.W. Scripps School of Journalism.