By Dr. Mercola
If you’re like most people, you’ve probably fallen for the misguided advice from most dermatologists and public health officials to stay out of the sun to avoid skin cancer. Unfortunately, total sun avoidance is inadvisable, as it can actually increase your risk rather than lower it.
Vitamin D, which is metabolized when UV rays strike your skin, has been shown to reduce not only your risk of melanoma—the deadliest form or skin cancer—but also the most common types of cancer. According to Australian researchers, vitamin B3 (nicotinamide) may also offer protection for those who are prone to certain skin cancers.1,2
Vitamin B3 May Reduce Recurrence of Some Skin Cancers
As reported by NBC News:3
“The Australian researchers tested it on 386 people who had already been diagnosed with skin cancer - either squamous cell or basal cell carcinoma. These are extremely common and slow-growing cancers, much less serious than melanoma...
The volunteers took either two 500 mg vitamin B3 pills a day for a year, or a placebo. After a year, those who took the B3 were 23 percent less likely to have another cancer diagnosed...
The pills also reduced the numbers of pre-cancerous lesions called actinic keratosis. These thick, scaly patches of skin were reduced by 20 percent among the volunteers who took nicotinamide after nine months of treatment.”
Those who took nicotinamide started seeing results in about three months. However, the protection vaporized once they stopped taking the vitamin, so to reap the rewards, you’d have to continue taking it indefinitely.
It’s thought that nicotinamide works by helping repair DNA damage caused by excessive UV exposure, and by bolstering your immune system.
That said, at present the researchers only recommend the supplement to those who are prone to skin cancer. It’s still unknown whether it might confer protection against skin cancer among the general population.
Is Sunscreen the Best Way to Avoid Skin Cancer?
Most news outlets publicizing this study point out you need to use sunscreen to avoid skin damage and cancer. But as many vitamin D experts have noted, the advice to avoid the sun as much as possible can have equally if not greater adverse health effects.
Can UV radiation be dangerous? Yes. It can increase your risk for certain skin cancers such as squamous cell, and basal cell. But there are significant differences even between these cancers, and appropriate sun exposure may be more beneficial than detrimental in some cases.
As previously explained by Dr. John Cannell, one of the leading authorities on vitamin D and founder and executive director of the Vitamin D Council, squamous cell carcinoma is clearly associated with chronic sun exposure, and is more common on the face, hands, and scalp.
Melanoma, which is the deadliest form of skin cancer, is associated with sunburn, especially sunburns when you’re young, yet often appear on areas of your body that rarely if ever see the light of the sun. How can this be?
What often happens is that as people get older, their dermatologist will tell them they need to stay out of the sun because they’re starting to exhibit skin damage from a lifetime of sun exposure.
But once they shun the sun, they effectively prevent their bodies from working as nature designed it, and sun exposure is actually part and parcel of what helps keep skin cancer at bay...
Vitamin D is activated in your skin, and activated vitamin D influences the genes in your skin and helps prevent the type of abnormalities that ultraviolet light causes. As a result, sun avoidance becomes the factor that paradoxically triggers skin cancer.
In a nutshell, the vitamin D your body produces in response to UVB radiation is protective against melanoma. As noted in one Lancet study:4
"Paradoxically, outdoor workers have a decreased risk of melanoma compared with indoor workers, suggesting that chronic sunlight exposure can have a protective effect."
Regularly applying sunscreen effectively prevents vitamin D activation in your skin, thereby preventing it from offering the protection it will naturally provide. Adding insult to injury, when you apply sunscreen you may also be more apt to stay in the sun far longer than you might otherwise, thereby adding to the skin damage.
Evidence suggests a wiser strategy would be to get sensible unprotected sun exposure on a large amount of bare skin to the point just short of your skin turning pink, and then cover up with a thin layer of clothing.
It’s also wise to wear a wide-brimmed hat when you’re outdoors for longer periods of time, as the skin on your face is more prone to damage and will not add much to your vitamin D stores.
Two Decade-Long Study Finds Sun Avoidance Doubles Risk of Death
A Swedish study5 published last year followed nearly 30,000 middle-aged to older women for up to 20 years. The average follow-up was 15 years. At the outset, they asked a number of questions about sun exposure, such as: Do you sunbathe? Do you take vacations in sunny areas in the winter? Do you garden with short sleeves and shorts? And, do you use sunbeds? What they discovered was that women who avoided the sun were twice as likely to die over the course of the study.
The researchers attributed this finding to the influence of vitamin D. What this study shows is that chronic sun exposure appears to be associated with less mortality. It’s also the first study to show that women who use tanning beds live longer than those who don’t. This is in direct conflict with what almost every dermatologist will say, including the former US Surgeon General, who was a dermatologist. It’s unfortunate, but the danger of almost any specialist is that they fail to take the broader perspective.
Dermatologists see and treat the effects of UV overexposure every day, and therefore tend to ignore or minimize the other side of the equation, which is that sun exposure has a wide array of health benefits—one being a reduction in overall mortality as evidenced in this study. Such benefits are easily overlooked though, since no one will think to attribute a longer life and/or absence of disease to the fact that they spent time in the sun!
The Case for Safe, Sensible Sun Exposure
The number of studies attesting to the health benefits of vitamin D is now in the thousands. This includes a reduced risk of about 16 different cancers, including pancreatic, lung, ovarian, breast, prostate, and skin cancer. There are well over 800 references in the medical literature showing vitamin D's effectiveness against cancer alone, and the evidence suggests this reduction is around 50 percent. One Canadian study6 found that women who reported having the most sun exposure as a teenager and young adult had close to a 70 percent reduced risk of developing breast cancer.
Another study7,8 published in 2013 found women whose serum levels were below 10 ng/ml had six times the risk of breast cancer compared to those whose levels were above 20 ng/ml, and a 2014 study,9,10 which looked at Iranian women, found a 1,000 percent increase in the risk of breast cancer among those who covered themselves completely, thereby getting no exposure to sunlight! From my perspective, it’s insane not to take advantage of this natural cancer prevention strategy for fear of skin cancer.
Dr. William Grant of Sunlight, Nutrition, and Health Research Center (SUNARC) estimates that if everyone in the US had a vitamin D level of 40 nanograms per milliliter (ng/ml), it would save approximately 150,000 lives a year.11 That’s 100 times the rate of squamous cell cancers, which is the only type of skin cancer definitively linked to chronic UV exposure.
Current recommendations place hundreds of thousands of people at greater risk for internal cancers, as opposed to 10,000 people who are dying from skin cancer caused by sunburn. Not only that, vitamin D is also known to provide many other health benefits, all of which are negated if you wholly abstain from sun exposure. For example, vitamin D helps support healthy:12
- Immune function
- Kidney function
- Teeth and bones
- Cardiovascular system
- Brain function
Understand the Risks and Benefits of Sun Exposure
When it comes to sun exposure, it’s really a matter of making an educated risk-benefit analysis, and I believe it’s possible to optimize your benefits while minimizing your risk by getting safe, sensible sun exposure, and avoiding sunscreen. If dermatologists were indeed correct about using sunscreen to avoid melanoma, incidence should have decreased right along with the increase in sunscreen. Alas, over the past 30 years, as sunscreen use has risen, so has incidence of stage 1 melanoma.
Besides blocking the activation of vitamin D, many sunscreens also contain toxic ingredients, which is the last thing you need to slather on your skin if you’re concerned about your health. Making matters worse, sunscreens containing vitamin A and its derivatives (retinol and retinyl palmitate), and other hazardous ingredients such as oxybenzone, have been shown to increase the speed at which malignant cells develop and spread skin cancer.
Another important factor to remember is that SPF only protects against UVB rays, which are the rays within the ultraviolet spectrum that allow your body to produce vitamin D in your skin. But the most dangerous rays, in terms of causing skin damage and cancer are the UVA rays. So make sure any sunscreen you buy protects against UVAs as well as UVBs.
Five Tips for Safe and Sensible Sun Exposure
You definitely want to be very careful and always avoid getting burned-- virtually all of the harm from sun exposure is related to sunburn—but you also want to avoid shielding yourself from the sun entirely. Here are a few tips to help you reap maximum rewards while minimizing your risks:
- Expose large amounts of your skin (at least 40 percent of your body) to sunlight for short periods daily. If using a sunscreen, give your body a chance to produce vitamin D before you apply it, and be sure to select a non-toxic sun lotion that protects against both UVB and UVA rays. The Environmental Working Group offers a comprehensive “Guide to Sunscreens”13
- Stay out just long enough for your skin to turn the very lightest shade of pink, if you’re naturally light-skinned, or just a hint reddish if you’re dark-skinned. Shield your facefrom the sun using a safe sunscreen or hat, as your facial skin is thin and more prone to sun damage, such as premature wrinkling.
- When you'll be in the sun for longer periods, cover up with clothing, a hat, or shade (either natural or shade you create using an umbrella).
- Consider the use of an "internal sunscreen" like astaxanthin to gain additional sun protection. Astaxanthin is a potent antioxidant (and pigment) produced by marine algae in response to their exposure to UV light. Typically, it takes several weeks of daily supplementation to saturate your body’s tissues enough to provide protection.
- Consuming a healthy diet full of natural antioxidants is another useful strategy to help avoid sun damage. Fresh, raw, unprocessed vegetables and fruits deliver the nutrients that your body needs to maintain a healthy balance of omega-6 and omega-3 oils in your skin, which is your first line of defense against sunburn. Vegetables also provide your body with an abundance of powerful antioxidants that will help you fight the free radicals caused by sun damage that can lead to burns and cancer.