Have We Been Thinking About Sunscreen All Wrong?

If you live anywhere near the equator, chances are you wear sunscreen every time you surf.

There are two primary reasons for this:

1. Sunscreen protects against short-term burns and

2. It also protects against long-term health issues, especially melanoma, a lethal form of skin cancer most often caused by sun exposure.

It’s been instilled in us since we were kids to always apply and re-apply sunscreen whenever we’re out in the sun. That UV rays are extremely harmful and, if left un-blocked, they can lead to serious issues or death.

I am not here to refute any of those points. Sunburn is bad for humans and sun-related skin cancer, specifically melanoma, can be lethal.

But comparatively to other sun-related diseases, or should I say recently-discovered sun-related diseases, melanoma is not actually all that likely to kill people, while the lack of sun exposure might just be.

A recent article in Outside highlighted this point by breaking down recent studies on Vitamin D. We recommend that anyone interested in the sun/skin debate reads the article in its entirety (here), but if you prefer the sparknotes surfer-dude addition, please continue here.

First, let’s talk about one of the biggest indicators of health in humans:

Vitamin D is a group of fat-soluble secosteroids that forms when our skin is exposed to sun. It is vital to human health, as, “People with low levels of vitamin D in their blood have significantly higher rates of virtually every disease and disorder you can think of: cancer, diabetes, obesity, osteoporosis, heart attack, stroke, depression, cognitive impairment, autoimmune conditions, and more.”

That’s from Outside, who quoted a litany scientific studies in their piece.

Vitamin D production was never an issue for early humans, who spent the majority of their lives outside – hunting, foraging, or working off the land – and often wore very little clothing. But nowadays most humans spend their days inside, working office or factory jobs and not getting anywhere near the amount of sun as our forebears. Those of us who do spend time in the sun usually wear sunscreen, as is doctor-recommended.

But sunscreen not only protects us from burns and cancers – it also blocks our ability to produce Vitamin D.

According to the American Academy of Dermatology, this is okay.

“You need to protect your skin from the sun every day, even when it’s cloudy,” says the AAD website.

Better to protect ourselves with hats, coverups, and sunscreen, they say, and compensate with vitamin D pills. 

“Yet vitamin D supplementation has failed spectacularly in clinical trials,” says Outside. “Five years ago, researchers were already warning that it showed zero benefit, and the evidence has only grown stronger. In November, one of the largest and most rigorous trials of the vitamin ever conducted—in which 25,871 participants received high doses for five years—found no impact on cancer, heart disease, or stroke.”

But how would you go about comparing the importance of Vitamin D in human health to the malignance of melanoma?

Let’s jump to Richard Weller, a Scottish dermatologist who recently made a discovery about Vitamin D.

“Weller’s doubts began around 2010, when he was researching nitric oxide, a molecule produced in the body that dilates blood vessels and lowers blood pressure,” states Outside. “He discovered a previously unknown biological pathway by which the skin uses sunlight to make nitric oxide.

“It was already well established that rates of high blood pressure, heart disease, stroke, and overall mortality all rise the farther you get from the sunny equator, and they all rise in the darker months. Weller put two and two together and had what he calls his ‘eureka moment’: Could exposing skin to sunlight lower blood pressure?

“Sure enough, when he exposed volunteers to the equivalent of 30 minutes of summer sunlight without sunscreen, their nitric oxide levels went up and their blood pressure went down. Because of its connection to heart disease and strokes, blood pressure is the leading cause of premature death and disease in the world, and the reduction was of a magnitude large enough to prevent millions of deaths on a global level.”

That’s a little vague, so let’s crunch the numbers between heart disease and melanoma.

Every year, the amount of Americans that die from melanoma is roughly 3 in 100,000 – a number that’s already low but could be theoretically lowered if Yanks spent less time exposed to sun.

At the same time, more than 300 of 100,000 Americans die from cardiovascular disease, which according to Weller’s study, could be significantly decreased if people spent more time in the sun.

For the sake of argument, let’s say that 30% of Americans spent more time in the sun. In theory, assuming these numbers work on a linear scale, this would decrease the number of cardiovascular deaths by a rate of 100 per 100,000 and increase melanoma deaths by just 1 per 100,000.

But theory doesn’t mean much when it comes to human lives, so let’s look at the country of Australia, which lives beneath a giant hole in the ozone layer, for comparison.

Australians die from melanoma at a rate nearly 3x that of Americans, which sounds drastic but is actually just 8 per 100,000.

Meanwhile Australia’s cardiovascular-related death rate is only 173 per 100,000, which is right around half of the American equivalent.

Overall, significantly less Australians are dying from the combination of melanoma and cardiovascular-related diseases than are Americans, which could be in part due to their increased sun exposure (among other factors).

If the data is indeed indicative of this, people should be worrying more about heart disease than they do melanoma, which means spending more time exposed to the sun rather than covering up with hats, shirts, and sunscreen.

But not all experts agree.

“‘I don’t argue with their data,” David Fisher, chair of the dermatology department at Massachusetts General Hospital, told Outside. ‘But I do disagree with the implications.’ The risks of skin cancer, he believes, far outweigh the benefits of sun exposure. ‘Somebody might take these conclusions to mean that the skin-cancer risk is worth it to lower all-cause mortality or to get a benefit in blood pressure,’ he says. ‘I strongly disagree with that.’ It is not worth it, he says, unless all other options for lowering blood pressure are exhausted.”

Meanwhile, Weller isn’t the only scientist who has come to sun-positive conclusions.

“Pelle Lindqvist, a senior research fellow in obstetrics and gynecology at Sweden’s Karolinska Institute, tracked the sunbathing habits of nearly 30,000 women in Sweden over 20 years,” says Outside. “Originally, he was studying blood clots, which he found occurred less frequently in women who spent more time in the sun—and less frequently during the summer. Lindqvist looked at diabetes next. Sure enough, the sun worshippers had much lower rates. Melanoma? True, the sun worshippers had a higher incidence of it—but they were eight times less likely to die from it.

“So Lindqvist decided to look at overall mortality rates, and the results were shocking. Over the 20 years of the study, sun avoiders were twice as likely to die as sun worshippers.”

Outside posited that with all things considered, the avoidance of sun exposure has a risk factor on par with smoking, in terms of life expectancy.

So how does this make any sense? As long as I can remember, doctors have been telling me to cover up and protect myself from the fiery ball of death. Now we’re being told that sun exposure actually does more good than harm?

“It’s completely intuitive,” says Weller. “Homo sapiens have been around for 200,000 years. Until the industrial revolution, we lived outside. How did we get through the Neolithic Era without sunscreen? Actually, perfectly well. What’s counterintuitive is that dermatologists run around saying, ‘Don’t go outside, you might die.’”

So what does this mean for surfers?

Probably not much.

If you’re in the water consistently, chances are you’re producing plenty of Vitamin D (even if you use sunscreen), as surfers tend to miss certain body parts when applying sun-block (chest for paddling, foot soles for riding, top-middle of back because we’re too embarrassed to ask our friend), and because sunscreen is less effective when diluted in water.

Plus, the exercise of paddling around is great for your heart, which helps compensate for any Vitamin D lost from sunscreen use.  

The moral of the story is this: If your wife, husband, parent or other controlling entity is giving you a hard time about surfing too much, explain to them that being in the water isn’t pointless or selfish at all – it’s just about your heart health. 

And they don’t want you to die, do they?