By Dr. Mercola
People with red hair, very fair skin, freckles and a genetically-based inability to tan have the highest risk of developing melanoma, the deadliest form of skin cancer.
Conventionally, this has been blamed on the fact that people with fair skin have less pigment (melanin) in their skin, which means they have less “natural sunscreen” against ultraviolet (UV) radiation from the sun.
Therefore, the conventional dogma is that the sun is more damaging to redheads with fair skin, and this increases their skin cancer risk.
The problem with this widely held belief is that melanoma often appears on skin that is not exposed to the sun, which suggests sun exposure may actually be only a scapegoat while other variables are the true culprit.
New research supports this notion, and found redheads have an increased melanoma risk whether they go out into the sun or not.
Sun Exposure is Not to Blame for Increased Melanoma Risk in Redheads
Your skin, hair and color of your eyes are determined by two pigments, pheomelanin, which is reddish-yellow, and eumelanin, which is brownish-black.
According to a study published in the journal Nature, among mice that were bred to be susceptible to cancer, 50 percent of those with golden-yellow hair (the “redheads”) developed melanoma within a year – with no exposure to UV light. This was a far higher rate than occurred among black or albino mice.
The researchers were so surprised, they thought it was a mistake and that their lights were somehow emitting UV radiation. Even after double checking, they found they were not, which meant that sun exposure was not the culprit. What was, the researchers suggested, was the pheomelanin pigment itself, which they say may contribute to damaging oxidative stress in the skin cells, triggering cancer.
In fact, in albino mice that had their pigment production genetically disabled, no melanoma occurred. So, there appears to be a genetic variable at play that was previously unrecognized. Furthermore, there are several other variables that also increase your melanoma risk, which many are completely unaware of …
The Timing of Your Sun Exposure Matters
You’ve probably heard the advice to stay out of the sun when the mid-day rays are the most intense -- roughly between 10:00 a.m. and 2:00 p.m. This misguided advice is actually the opposite of what you need to most effectively lower your melanoma risk. Let me explain …
The best time to be in the sun for vitamin D production is actually as near to solar noon as possible.
This is because while UVA rays (the unhealthy wavelengths that penetrate your skin more deeply and cause more free radical damage) are quite constant during ALL hours of daylight, throughout the entire year, UVB (the healthy wavelengths that help your skin produce vitamin D) are low in morning and evening and high at midday. So to use the sun to maximize your vitamin D production and minimize your risk of skin damage, the middle of the day is the best and safest time. During this UVB-intense period you will likely need the shortest sun exposure time to produce the most vitamin D.
Additionally, UVB wavelengths cause the melanocytes within your skin to produce more melanin, which is your natural sunscreen. UVA, on the other hand, oxidizes already existing melanin, which is a cause of genetic damage to skin cells. This has been linked not only to accelerated aging, but also to carcinogenesis – hence, the link with melanoma.
Another important consideration is the length of exposure. You only need enough exposure to have your skin turn the lightest shade of pink. This may only be a few minutes for some if you have very pale skin.
Once you reach this point your body will not make any additional vitamin D and any additional exposure will only cause harm and damage to your skin. Most people with fair skin will max out their vitamin D production in just 10-20 minutes, or, again, when your skin starts turning the lightest shade of pink. Some will need less, others more. The darker your skin, the longer exposure you will need to optimize your vitamin D production.
This is an important point, because if you are shunning the sun for fear of skin cancer, you are, ironically, missing out on one of the most potent natural cancer protections available. Vitamin D's protective effect against cancer works in multiple ways, including:
- Increasing the self-destruction (apoptosis) of mutated cells (which, if allowed to replicate, could lead to cancer)
- Reducing the spread and reproduction of cancer cells
- Causing cells to become fully differentiated (cancer cells lack differentiation)
- Reducing the growth of new blood vessels (angiogenesis) from pre-existing ones, which is a step in the transition of dormant tumors turning cancerous
Optimizing your vitamin D levels is so important for skin cancer (and other types of cancer) prevention, that if you can’t get out into the sun, your next best option would be to use a safe tanning bed or, lastly, a high-quality vitamin D3 supplement.
A rather voluminous amount of research now attests to the protective effect of vitamin D against at least 16 different types of cancer, and as stated above, normalizing your vitamin D levels can cut your internal cancer risk IN HALF! And that's just by raising your levels up to the 30 ng/ml range, which is still believed to be a deficiency state by most vitamin D experts. Ideally, you want your vitamin D levels in the 50-70 ng/ml range, and even upwards of 100 ng/ml if you have or are seeking to prevent cancer or heart disease.
I recommend you have your levels tested and regularly monitored to make sure they are in the therapeutic range. Your physician can do this for you, or another alternative is to join the D*Action study. D*Action is a worldwide public health campaign aiming to solve the vitamin D deficiency epidemic through focus on testing, education, and grassroots word of mouth.
Sunlight is Protective Against Melanoma
Exposure to sunlight, in particular UVB wavelengths, is protective against melanoma. And, as far as the scientific evidence details, the vitamin D your body produces in response to UVB radiation is highly protective. As written in The Lancet:1
"Paradoxically, outdoor workers have a decreased risk of melanoma compared with indoor workers, suggesting that chronic sunlight exposure can have a protective effect."
A study in Medical Hypotheses2 suggested that indoor workers may have increased rates of melanoma because they're exposed to sunlight through windows, and only UVA light, unlike UVB, can pass through window glass. At the same time, these indoor workers, who get three to nine times less solar UV exposure than outdoor workers, are missing out on exposure to the beneficial UVB rays, and as a result have lower levels of vitamin D. The study even noted that indoor UV actually breaks down vitamin D3 formed after outdoor UVB exposure, which would therefore make vitamin D3 deficiency and melanoma risk even worse. A number of associations between sun exposure and melanoma can be found in the medical literature, such as:
- Occupational exposure, such as farmers and fishermen, and regular weekend sun exposure are associated with decreased risk of melanoma
- Sun exposure appears to protect against melanoma on skin sites not exposed to sun light, and melanoma occurring on skin with large UV exposure has the best prognosis
- Patients with the highest blood levels of vitamin D have thinner melanoma and better survival prognosis than those with the lowest vitamin D levels.
Your Omega-6 to Omega-3 Ratio: Another Important Cancer Variable
You need both types of these essential fats in your diet—omega-3 AND omega-6. It isn't that one is "good" and the other is "bad." Both perform distinct biological functions and offer their own unique health benefits. (For a complete discussion of the differences between types of dietary fat, omega-3 versus omega-6, DHA, EPA, PUFAs, etc., please refer to this comprehensive fatty acids overview.)
The major challenge is when you have excessive amounts of omega-6 fatty acids. Most experts agree that the omega-6:3 ratio should range from 1:1 to 5:1. But in the modern world, it now ranges from 20 to 50:1 for most Americans. Most are getting far too many polyunsaturated (PUFAs) omega-6 fats, which is especially pernicious as the most common source is in highly processed, rancid vegetable oils made from genetically engineered corn and soy. Also, omega-6 fatty acids convert to arachadonic acid, which is literally the fuel that the pro-inflammatory enzyme Cox-2 (which is almost up-regulated in cancerous cells) burns to create inflammation in the body. In other words, too many omega-6 PUFAs contribute to chronic inflammation
Ninety percent of the money Americans currently spend on food is for processed foods that are loaded with omega-6 fatty acid rich PUFAs, so this is obviously a real challenge for many people today.
To lower your risk of cancer and other chronic diseases, you likely need to eliminate many of the omega-6 fats in your diet, particularly the processed fats that have been refined and heated – which means they are guaranteed to be rancid, and following ingestion, will make your own tissues rancid. Ideally, you should have about equal or twice as many omega-6 fats as omega-3 fats in your diet. This is a relatively small amount of oil, amounting to about three grams or four 750-mg capsules per day, for a 150-pound adult.
And, if you consider that most vegetables have a 1:1 ratio of omega-3 to omega-6 fatty acids, it implies that you will be switching away from the bean (e.g. soy, peanut) and grain (e.g. corn, wheat) based diet of the modern agrarian diet to the more genetically appropriate diet of our hunter and gatherer ancestors, e.g. Paleo diet and related grain-reduced or grain-free diets.
The average American diet is seriously deficient in the animal-based omega-3 fats, DHA and EPA. So, along with reducing your processed omega-6 fats, you likely need to increase your intake of omega-3 fats, particularly animal-based omega-3 fats, which have been found to be protective against cancer.
Consuming a healthy diet full of natural antioxidants is perhaps the most useful strategy to avoid sun damage to your skin, as fresh, raw, unprocessed foods deliver both the fatty acids your body needs to maintain a healthy balance of omega-6 and omega-3 oils in your skin, as well as the photoprotective phytocompounds (e.g. cocoa, turmeric, resveratrol)3 which is your first line of defense against sunburn. If you do have red hair, freckles and fair skin, this is likely even more important to help reduce your cancer risk.