Vitamin D is a fat soluble vitamin that is made in your body after exposure to ultraviolet B (UVB) rays from the sun. For some time now, the media has been bombarding Americans with reports of the dangers of the sun causing skin cancer. In recent years, there is increasing evidence that the dangers of sun exposure have been greatly exaggerated and the benefits highly underestimated. Sun exposure is not the major reason people develop skin cancer. I know this might surprise many of you as this is opposite to what you have been told in the past.

So can sun exposure cause skin cancer? Absolutely, sun exposure should only be implemented very gradually. (See Safe Tanning Guidelines below.) However, the recommendation to never go out in the sun without wearing sunscreen is simply misguided advice. You can still develop sun damage even with sunscreen; sunscreens don't stop the damage from occurring on a cellular level, they simply stop the burn. In addition, sunscreens with a sun protection factor (SPF) of 8 or higher will block UVB rays that help your body's ability to synthesize vitamin D.

A Healthy Diet Can Help Prevent Sunburn

The amount of antioxidants that you have in your skin plays a major role in your development of sunburn. The more antioxidants you take in, the lower your risk of sunburn. Foods containing effective antioxidants to boost your "internal sunscreen" include fresh vegetables and fruits such as Goji berries (not the juice), blueberries, raspberries, and blackberries. Vitamins A and C are also vital as your cells use these vitamins to regulate both light absorption and protection against overexposure.

Moreover, increasing the omega-3:6 ratios in your diet is an incredibly important way to prevent skin cancer. Right now most Americans are eating far too many omega-6 fats and far too little omega-3. The primary source of omega-6 fats are processed vegetable oils made from corn, soy, safflower and sunflower seeds, whereas, omega-3 fats are found in fish oil and cod liver oil. Please refer to the February 2008 newsletter on this topic.

Benefits of Vitamin D

Vitamin D works with calcium to keep bones strong and prevent osteoporosis. There is also strong evidence that it maintains a healthy immune system and reduces the risk of some common cancers (breast, colon, pancreatic, lung, ovarian, and prostate), multiple sclerosis, diabetes, heart disease, hypertension, inflammatory bowel disease, rheumatoid arthritis, and age-related muscle weakness.

Vitamin D deficiency causes rickets in children and osteomalacia in adults. Rickets is a bone disease that results in soft bones and skeletal deformities. Osteomalacia results in muscular weakness, bone pain, and weak bones.

D Basics

Vitamin D is unique in that your skin manufactures it just by being exposed to UVB rays from the sun. The ultraviolet A (UVA) rays produce a tan that not only makes your skin more pleasing in appearance, but is also your body's natural defense against sunburn. Vitamin D is fat soluble, the body can store it for the months when you don't get any sun or consume any D. The amount made depends on a number of factors such as:

·         Age - older people produce less D

·         Skin color - a person with dark skin needs more sun exposure to produce the same amount as a person with pale skin

·         Latitude - the further north you are, the less UVB there is

·         Altitude - the higher up you are, the more UVB reaches you

·         Cloud cover and pollution - can block UVB

Vitamin D exists in several forms, each with a different level of activity. D3 (cholecalciferol) is the most potent and is the natural form found in foods

and made by the skin when exposed to sunlight. D3 is also the major circulating form of vitamin D in your body.

Many researchers believe that the goal for most Americans, especially those over 60 and/or with darker skin is 1,000 IU a day. In 2007, the American Journal of Clinical Nutrition concluded that D is not toxic up to 10,000 IU a day.

When careful sunlight exposure is not possible and when sufficient vitamin D is not consumed in the diet, you should consider taking a supplement. Likewise, if your latitude is above 30 degrees north or below 30 degrees south, you will likely benefit from vitamin D supplementation from September to mid April. When shopping for a supplement, always look for D3 which is far superior and more potent than the synthetic D2 (ergocalciferol).

Testing For Vitamin D

Since the body's ability to make and utilize D varies from person to person, testing can be important. The correct test your doctor needs to order is 25(OH)D, also called 25-hydroxyvitamin D. He/she may say it isn't necessary as it costs about $100 and insurance may not pay for it unless you have osteoporosis or another condition potentially related to vitamin D deficiency.

The optimal value that you are looking for is 45-50 ng/ml.

Although D lab values of 20-56 ng/ml are considered "normal", your level should never be below 32 ng/ml and any levels below 20 ng/ml are considered serious deficiency states and will increase your risk of breast and prostate cancers and autoimmune diseases like multiple sclerosis and rheumatoid arthritis.

Safe Tanning Guidelines

If your skin is unused to the sun, it is important to build up your tolerance regularly and gradually. It is good to start early in the year, in the spring and early summer. This will prepare your skin for the stronger sunlight later in the year.

At the beginning of the season, go out gradually and 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 of skin cancer.

·         Early morning is the best time to sunbathe if you have not already built up a base tan. You're less likely to burn in the mild sun than later in the day.

·         Regular sunbathing, i.e. frequent, short exposures, is critical. You cannot cram all your sun exposure into a one week vacation and expect to experience the benefits.

·         For optimal result, strive to have at least 40% of your skin uncovered. Merely exposing the face and hands is insufficient to bring vitamin D levels to the optimal range of 45-50 ng/ml.

·         In Caucasian skin, equilibrium occurs within 20 minutes of ultraviolet exposure, further increases in vitamin D is not possible. For darkly pigmented skin, it can take 3-6 times longer to reach the same equilibrium. If you have light-colored skin, stay out just long enough so that your skin turns the very lightest shade of pink, then it's time to get in the shade or cover up with clothes.