Benefits of Safe Sun Exposure for Reduced Cancer Risk
There are few topics I could write about that would be as controversial as that of safe sun exposure. Perhaps vaccines and why I don’ reduce a fever, but based on current research, this topic may be one of the most important ones that isn’t getting nearly enough attention.
Sunbathing and tanning often get a bad rap in our society, but mounting evidence is revealing that moderate sun exposure at healthy levels is not only safe, but necessary. Burning and extreme sun exposure are harmful and can lead to increased cancer risk. But moderate sun exposure doesn’t increase this risk. Vitamin D (obtained from sun exposure) has been linked to a lower risk of many cancers (including skin cancer).
In fact, the most recent in-depth review found that avoiding the sun was a risk factor for all-cause mortality of the same magnitude as smoking.
In other words: avoiding the sun may be as dangerous as smoking cigarettes!
First, Let’s All Take a Deep Breath… As I said, this is a controversial topic. I’m sharing what I’ve found from research and blood tests on myself and my family. I’m not a doctor and don’t play one on the internet or anywhere else. I just read a lot of studies for fun and am sharing a couple of really fascinating new ones here.
Let’s just all agree to play nice in the comments. Ok?
Even if we disagree, please comment with respect. Let’s also remember that anecdotal evidence doesn’t prove anything.
Examples of anecdotal evidence:
- You know someone who died from skin cancer, therefore you think all sun exposure is bad. (Even though science doesn’t back this up and that scenario doesn’t prove causation).
- You know someone who has been outside every day of his or her entire life and got sunburned all the time and never got cancer, therefore all sun exposure is safe. (Science also doesn’t back this up).
We all know people who have been affected by cancer and many hugs to all of you who have lost someone to this dreaded disease. That does not, however, equal a scientific study. I know someone who has never gotten sun exposure, wears a hat and sunscreen daily, and still got skin cancer on his nose. This is also not scientifically relevant.
That said, the current evidence is showing that some levels of sun exposure are safe. Ironically, some reserach indicates that some sunscreen ingredients may be increasing skin cancer.
But read on:
Sunscreen, Sunburn and Skin Cancer, Oh My
In the last several decades, the push to use sunscreen and limit exposure to the sun has gotten stronger. It is now possible to find SPF 70 or higher! Thanks to massive campaigns, most people are at least mildly aware of the “dangers” of sun exposure.
Except for sun exposure may not be as dangerous as we think! And avoiding the sun may be the dangerous part.
Despite the push for more awareness about sun exposure, and the advice to use sunscreen whenever we go outside, incidence of skin cancer, especially melanoma, is rising dramatically.
In fact, skin cancer rates are rising by 4.2% annually, despite the fact that we spend less time outdoors and wear more sunscreen. We are doing the things we are “supposed” to do and the problem is getting worse.
But is Sun Exposure the Reason?
Here’s where things get interesting…
Perhaps the problem isn’t lack of sunscreen, or even sun exposure at all, but a deeper cause.
A recent in-depth scientific review found that while sunburn is harmful, moderate non-burning sun exposure (without sunscreen) had many benefits.
Recently, however, scientific inquiry has increasingly turned to the benefits of moderate sun exposure and the public health risks of inadequate sun exposure.
In Other Words:
Not getting ENOUGH sun can be just as harmful (or more so) than too much. Like so many things in life, the dose makes the poison.
And, Sunscreen May NOT Help Avoid Cancer
The general idea is that since sunscreen prevents sunburn, it also logically prevents skin cancer. Seems logical, but science doesn’t back this up! Also, sunscreen may block some of the most beneficial aspects of sun exposure. It may slow burning but it also blocks Vitamin D, and vitamin D deficiency is epidemic.
The scientific review also found that: “We can find no consistent evidence that use of chemical sunscreens reduces the risk of melanoma.”
The review authors even went so far as to suggest that sunscreen carry a warning label!
Since public health authorities recommend liberal use of sunscreens for good health, the labeling of sunscreens should contain a statement about the possibility of Vitamin D deficiency that may result from excessive use of sunscreens. Labeling should also state that sunscreens have not been shown to be effective in reducing the risk of melanoma.
Another study in the Journal of Clinical Pharmacology and Therapeutics found a similar result:
Sunscreens protect against sunburn, but there is no evidence that they protect against basal cell carcinoma or melanoma. Problems lie in the behavior of individuals who use sunscreens to stay out longer in the sun than they otherwise would. Vitamin D inhibition is, at this stage, unlikely due to insufficient use by individuals. Safety of sunscreens is a concern, and sunscreen companies have emotionally and inaccurately promoted the use of sunscreens.
Sunscreen DOES Block Vitamin D
Avoiding sunburn is certainly a good idea. The idea that sunscreen is the best way to do so is certainly up for debate.
We know that sunscreen inhibits Vitamin D production, especially when used regularly and that Vitamin D deficiency has been strongly linked to a variety of cancers, including two of the most common and most dangerous: breast and colon cancer.
So as a society we avoid the sun, even though we need sun exposure to help our bodies naturally produce Vitamin D. Then we put chemical laden lotions (sunscreen) on in hopes of reducing one type of cancer (skin cancer). In the process, we might make ourselves Vitamin D deficient and increase our chance of a host of other cancers, including some of the most common and dangerous ones.
And the study above showed that sunscreen doesn’t even prevent melanoma anyway!
Vitamin D: Vital for Health
In many cases we are (sometimes literally) cutting off our noses to spite our face when it comes to the sun. One study at the Oslo University Hospital in Norway found that the benefits of sun exposure far surpassed any risk:
It can be estimated that increased sun exposure to the Norwegian population might at worst result in 200-300 more cancer from malignant melanoma deaths per year, but it would elevate the vitamin D status by about 25 nmol/l (nanomoles per liter) and might result in 4,000 fewer internal cancers and about 3,000 fewer cancer deaths overall.
That’s just good math…
Sun exposure might lead to a few hundred more melanoma deaths, but would potentially stop 3,000 other deaths. That means a net of 2,700-2,800 people would get to live if they didn’t avoid the sun. I’d take those odds personally (and I do, daily).
Other studies have found links between low-vitamin D levels and Parkinson’s Disease, bone disease, blood clots, diabetes, heart disease and high blood pressure. A recent study even found that regular sun exposure helped women to live longer. Yet another study found that regular sun exposure could cut breast cancer risk in half!
Vitamin D is Important for Pregnancy, Babies, & Kids
Vitamin D is also essential during pregnancy and nursing as adequate blood levels of Vitamin D have been linked to lower premature labor and overall complication risk. Low Vitamin D levels can put a mom at higher risk for gestational diabetes and can lead to bone or other problems for the baby. Another recent study found that pregnant women should get more sun to increase several health markers for themselves and their babies.
Pregnancy & Vitamin D
This article from the Vitamin D council explains the importance of Vitamin D during pregnancy. Optimal levels are above 30 ng/mL during pregnancy. Some doctors even recommend levels above 60 ng/mL for best health, especially during pregnancy.
But women aren’t even close to those levels:
- Dr. Joyce Lee and her colleagues at the University of Michigan found that 37 of 40 pregnant women had levels below 40 ng/mL, and the majority had levels below 20 ng/mL. More than 25% had levels below 10 ng/mL.
- Dr. Lisa Bodnar, a prolific Vitamin D researcher, found that of 400 pregnant Pennsylvania women; 63% had levels below 30 ng/mL and 44% of the black women in the study had levels below 15 ng/mL. Prenatal vitamins had little effect on the incidence of deficiency.
- Dr. Dijkstra and colleagues studied 70 pregnant women in the Netherlands, none had levels above 40 ng/mL and 50% had levels below 10 ng/mL. Again, prenatal vitamins appeared to have little effect on 25(OH)D levels, as you might expect since prenatal vitamins only contain 400 IU of Vitamin D.
They concluded that:
More than 95% of pregnant women have 25(OH)D levels below 50 ng/mL, the level that may indicate chronic substrate starvation. That is, they are using up any Vitamin D they have very quickly and do not have enough to store for future use. Pretty scary.
These chronic low Vitamin D levels during pregnancy can lead to increased risk of cesarean, preeclampsia, gestational diabetes and vaginal infection in the mother, and a higher risk of autism, mental disorders, infection, low birth weight, and heart/lung/brain problems among others.
Vitamin D for Babies & Kids
Babies and kids may also be suffering from vitamin D and sun deficiency. Adequate vitamin D levels are really important for growing children, and not just to avoid rickets. A lot of research links adequate Vitamin D levels in children to better mental and physical health.
“As a rule, in the absence of significant sun exposure, we believe that most healthy children need about 1,000 IU of vitamin D3 daily per 11 kg (25 lb) of body weight to obtain levels greater than 50 ng/mL.Some will need more, and others less. In our opinion, children with chronic illnesses such as autism, diabetes, and/or frequent infections should be supplemented with higher doses of sunshine or vitamin D3, doses adequate to maintain their 25(OH)D levels in the mid-normal of the reference range (65 ng/mL) — and should be so supplemented year-round (p. 868).”
Many kids aren’t even getting 1/4 of that on a good day, and when they do, it often comes from the less useable Vitamin D2.
Our whole family has tested our Vitamin D levels (including me during pregnancy and after) and even with moderate daily sun exposure, we were all low (in the high 20s or 30s). I work with a doctor to test and supplement (while still getting sun exposure) if it is necessary.
Why Safe Sun Exposure May REDUCE Cancer Risk
The most comprehensive current studies don’t recommend avoiding the sun. To the contrary, the recent review (read the full review here) concluded:
In this paper we review the current state of the science of the risks and benefits of sun exposure and suggest that public health advice be changed to recommend that all men, women and children accumulate sufficient non-burning sun exposure to maintain their serum 25hydroxyvitaminD [25(OH)D] levels at 30 ng/mL or more year-round.
The Review Also Found:
- Sunbathing without burning reduced the risk of melanoma. Non-burning sun exposure is associated with a reduced risk of melanoma. Sunburns are associated with a doubling of the risk of melanoma. This means that while we should avoid sunburn, sun exposure itself is associated with less risk of melanoma!
- Long term exposure may also protect the skin. “With respect to chronic non-burning sun exposure, it is thought that protection against sunburn and development of melanoma derives from photo-adaptation (increased melanisation and epidermal thickening) or from the induction of higher levels of vitamin D, or possibly both.”
- Vitamin D reduces cancer risk. Science already knew this, but the study specifically found that…”Vitamin D produced by UVB exposure is converted to the active form of vitamin D by its sequential metabolism in the liver to form the major circulating form of vitamin D, 25-hydroxyvitamin D [25(OH)D]. Evidence suggests that vitamin D that is produced in the skin can also be converted in the skin to its active form 1,25(OH)2D, thereby enhancing DNA repair and lowering cancer risk.”
- Lack of sun exposure may be driving the rising melanoma rates. The review found that sun exposure is not likely the cause of rising melanoma rates. In fact, the opposite may be true. Declining sun exposure may be to blame: “A more plausible explanation for the rise in melanoma incidence since 1935 may be the continually-increasing insufficient non-burning sun exposure and related increasing vitamin D deficiency/insufficiency, and the increasing sunburn prevalence experienced by the American public over the same time period.”
Vitamin D Deficient = More Likely to Die?
The scientific review also found a relevant link between Vitamin D and reduced risk of death. Basically, the higher a person’s Vitamin D levels, the less likely that person was to die. The review noted that those with adequate Vitamin D had less risk of death from heart disease and certain cancers.
Inadequate sun exposure was also linked to higher rates of dental cavities, eye problems, obesity, skin problems and more.
Does Diet Impact Sun Exposure Risk?
In the quest for an easy (and profitable) solution to skin cancer, mainstream medicine and media have recommended sunscreen and limiting sun exposure. At the same time, they’ve ignored any potential role diet can play in skin cancer formation or prevention.
Perhaps, since skin cancer rates are rising despite the highest rates of sunscreen use in history… it is time to look at alternative explanations.
In the same past few decades that skin cancer (and other cancer) rates have risen, some dietary factors have also changed, including: increased use of Omega-6 vegetable oils, higher consumption of processed foods, more chemical additives in foods, reduced consumption of saturated fats, increased grain consumption, etc.
Increased Omega-6 Vegetable Oil Consumption
Omega-6 oils like canola, cottonseed, vegetable, soybean, etc., are a very new addition to our diets. There is no biological need to consume oils in this state. Some evidence also shows that when these oils are consumed, they can be used in place of the saturated and monounsaturated fats the body needs for skin formation and actually lead to skin cancer.
In fact, some studies have shown that the high linoleic acid content in vegetable oils increases the instance of skin cancer and other cancers, and lowers the body’s ability to fight cancer. As the article explains:
Thus, the amount of linoleic acid in the diet as well as the balance between omega-6 and omega-3 determine the susceptibility of the skin to damage from UV rays. This is a very straightforward explanation for the beautiful skin of people eating traditional fats like butter and coconut oil. It’s also a straightforward explanation for the poor skin and sharply rising melanoma incidence of Western nations (source). Melanoma is the most deadly form of skin cancer.
While vegetable oil consumption has risen, saturated fat and Omega-3 fat consumption has dropped.
Reduced Saturated Fat and Omega-3 Fat Consumption
As Omega-6 oil consumption has risen, consumption of saturated fats and Omega-3 fats has declined. We’ve seen how well that’s worked out for us, but it turns out that it could have a pretty big impact on skin health, too.
The body needs healthy fats, including saturated fats and Omega-3 fats, to regenerate skin tissue. The body prefers these types of fats. If the body doesn’t get these fats (and many people don’t these days), it will use whatever it has available. It may even use Omega-6 fats, which are not the preferred fat for building skin and collagen.
Bottom Line: Time to Rethink Sun Exposure
Based on the largest review of evidence we have to date, it is time to re-think sun exposure. The idea that the sun causes skin cancer isn’t the full story. Believing that for the past 70+ years may be doing much more harm than good.
While we’ve avoided the sun to hopefully avoid skin cancer, our rates of other cancers are going up. Our rates of all-cause mortality are going up. And this review found that a lack of sun may be the reason.
Sun Exposure: What I Do
In light of this, and so much other evidence, I don’t personally avoid the sun. In fact, I make it a point to spend some time in the sun daily. I also test my Vitamin D levels, take supplemental Vitamin D too and don’t use harmful sunscreens.
I get out of the sun before I get close to burning. If I get enough sun exposure and want to stay outside, I just cover up and wear a hat. And for the first time in my adult life, my Vitamin D levels are in the healthy range. I also “eat my sunscreen” by eating a real food diet and taking specific supplements that help protect the body from the inside out.