"Dermatologists have looked at the rise in melanoma and panicked. But they aren't looking at the whole human being" says Dr Robert Heaney of Creighton University, Nebraska.
Taking the advice of health officials, the media and the shops would see us covered head-to-toe in high-factor lotion, donning big-brimmed hats and lurking in the shade when the sun comes out. This would be understandable if your only objective is to cut the number of cases of skin cancer. But of course as Dr Heaney points out, avoidance of melanoma is neither the beginning nor the end of the story.
What Is Vitamin D?
Vitamin D is made in the skin when 7-dehydrocholesterol reacts with ultraviolet light (UVB) upon direct exposure of the skin to sunlight. This photosynthesis of vitamin D evolved over 750 million years ago in phytoplankton and it played a critical role in the maintenance of a calcified skeleton in vertebrates as they left their calcium-rich ocean environment for land over 350 million years ago. It's a basal requirement of vertebrates that have evolved on land.
High blood pressure, tuberculosis, cancers, periodontal disease, multiple sclerosis, chronic pain, seasonal affective disorder, peripheral artery disease, cognitive impairment which includes dementia, memory loss and foggy brain, several autoimmune diseases including type 1 diabetes, macular degeneration, osteoporosis and rickets, joint disease, birth difficulties, autism, asthma, weight control, influenza - and more.
Vitamin D is so influential to our health because it's not just a vitamin; it's the only known substrate for a potent, pleiotropic (producing multiple effects) repair and maintenance hormone that serves multiple gene-regulatory functions in your body. In fact, it has been shown to influence more than 2,000 genes. Just one example of an important gene that vitamin D up-regulates is your ability to fight infections: it produces over 200 anti-microbial peptides, including an important broad-spectrum antibiotic.
While we instinctively know - and can feel - the health-generative properties of the sunshine, science is helping us understand why. There are countless studies showing almost limitless benefits. Just a few examples: Researchers from the Moore's Cancer Center at the University of California, San Diego (UCSD) recently concluded that increasing the intake of vitamin D3 throughout the world could easily prevent diseases - including 16 types of cancer - that would otherwise claim close to 1 million lives each year worldwide. Recently, the American Academy of Pediatrics doubled its recommendation for a daily dose of vitamin D in children, in the hope of protecting against a wide range of diseases, while promoting other health benefits. In fact, Researchers from the European Institute of Oncology in Milan, and the International Agency for Research on Cancer in Lyon recently reviewed 18 trials of more than 57,000 people and found that sufficient levels of vitamin D may lower your risk of dying from any cause.
So Where's The Rub?
There is no doubt that vitamin D is extremely important for good health. The controversy arises as a result of the fact that at least 90 per cent of the vitamin D in the body comes from direct skin exposure to sunlight: it's agreed that by far the best way of boosting the nutrient is to expose your body to sunlight, without sunscreen, at times when ultraviolet radiation is at its strongest: noon and early afternoon in spring and summer.
The skin produces about 10,000 international units (IU) of vitamin D in response to 20-30 minutes of summer sun exposure (time depending upon the pigmentation of the skin, it can be much longer). One portion of oily fish contains 320 IU (8 micrograms). Vitamin D supplements do exist but the recommended daily dose of a vitamin D supplement is 400 IU (10 micrograms); any more of this synthetic (as opposed to skin-manufactured) version is considered a risk by authorities because too much can cause kidney damage. Conversely, there is very little risk of overdose of Vitamin D from the sun because once equilibrium is reached, production is downgraded. Further, most supplements also contain the inferior Vitamin D2 rather than the D3 that comes from the sun.
Nobody disagrees with the fact that getting sunburn is a bad thing. But when it comes to staying healthy, it's hard to overstate the case for exposure of skin to direct sunlight. Sunscreens will effectively shield you from the sun's health benefits. It's also important to note that you can develop sun damage even with sunscreen because it doesn't stop the damage from occurring at a cellular level, it simply stops the burn (and also usually includes toxins that potentially put your health at risk).
How Can I Enjoy The Sun Without Being At Risk?
If you're going to be enjoying the sun unprotected, you will need to be very careful. While only you can determine your requirements and threshold, there are some basic guidelines you can follow to minimise your risk.
- The more antioxidants you take in, the lower your risk of sunburn - an internal sunscreen. Include whole fresh vegetables and fruits such as Goji berries (not the juice), Raspberries, Blackberries, and Blueberries. Vitamins A and C help your cells regulate both light absorption and protection against overexposure, which you can get from vegetables and fruit.
- Exposure of the face and hands to sunlight is not sufficient for vitamin D nutrition. For optimal benefit, strive to have at least 40 percent of your skin uncovered.
- Optimal Exposure Time - in Caucasian skin, equilibrium occurs within 20 minutes of ultraviolet exposure. It can take 3 to 6 times longer for darkly pigmented skin to reach the equilibrium concentration of skin vitamin D. Remember that continuing UV exposure beyond the minimal dose required to produce skin redness will not increase your vitamin D production any further.
- At the beginning of the season, limit your exposure to perhaps as little as 10 minutes a day. Progressively increase your time in the sun so that in a few weeks, you will be able to have normal sun exposure with little risk.
- Regular sun is extremely important. You can't cram all of your sun exposure into a two or three week vacation period and expect to experience the benefits... and it's safer not to try! Frequent, short bursts are best.
- Time of Day - Early morning is the best time to sunbathe if you have not already built up a base tan, because you're less likely to burn. In addition, it's best to sunbathe when the temperature is not too high, so that you don't over heat.
- Supplement vitamin D. If you are unable to get enough from the sun due to your lifestyle or where you live, a good quality vitamin D3 supplement can help
With any luck, this article will have cleared up some of the confusion around sun exposure, its risks and its benefits. So get out there and start enjoying the sunshine!
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