Get your tan at high noon, not in bed.

     For years the medical profession has told us that we should stay out of the sun during mid-day hours when the sun is at its peak, and that maybe getting our sun for Vitamin D synthesis in the early to mid morning or late afternoon would be better.

     Keep in mind that sunlight has two components that affect skin: UVA (ultraviolet A) light is the component that damages and ages skin.  UVB (ultraviolet B) light is the component that helps synthesize natural Vitamin D in our skin.  Both UVA and UVB can cause tanning and burning, although UVB does so far more rapidly. UVA, however, penetrates your skin more deeply than UVB, creates more free-redical damage and may be a much more important factor in the photoaging that causes wrinkles and promotes skin cancers.  A short word about tanning beds: avoid if at all possible.   They emit more UVA than UVB, and are a higher risk for skin damage.

     About 10-20 minutes of mid-day sun will max out your Vitamin D production, although if you live north of Miami, this is less true in winter.  While UVA exposure is much the same throughout the daylight hours, UVB is at a maximum at mid-day.  So the tradeoff between skin aging vs Vitamin D production is actually best at mid-day.  The key is: not too much of a good thing.  If you get mid-day sun, start with short periods of exposure, 5-10 minutes and work up to 10-20 minutes, but not enough to pink your skin.

     While dietary or supplementary Vitamin D3 may be the only practical way that indoor workers or those at northern latitudes get their year-round Vitamin D levels up, the natural, or skin-produced Vitamin D3 is actually the better version.  Vitamin D3 reduces the incidence of most every cancer, particularly colon, breast and skin through several mechanisms.  One large population study showed a 60% across the board cancer reduction with optimal Vitamin D levels.  The only way to know your level is to get a blood test for D3 level, which should be in the 50-70 range.

Further food for thought:

     While recent theories paint sun exposure as the cause of skin cancer like melanomas, it is interesting to note that 1) in 1900, about 75% of the U.S. population worked outdoors. melanoma was rare. But since the 1970s, the incidence of melanoma has been steadily rising. It is rising at a time when sun exposure is decreasing, also correlating a time frame when vitamin D deficiencies are becoming epidemic.  2) melanoma is more common in indoor workers than outdoor.  It is more a disease of office workers than farmers.  3) melanoma is more common on regions of the body that are not exposed to the sun.  4) melanoma is the second leading cause of cancer death for people age 15 to 30, and that rate is increasing. 

Another important factor that has changed drastically in the last 40 years; one that would also account for melanoma striking younger people, is diet.  Dr. John Cannell of the Vitamin D Council comments on this: “Diets rich in vegetables, fruits, and omega-3 fats – the absence of appreciable quantities of omega-6 and trans-fats – protects your skin from burning. The people who get sunburned are modern humans who live and work indoors, avoid fruit and vegetables, love french-fries and chips, dislike salmon, and go to the beach two or three times in the summer to roast themselves. Frequent sunburns, especially in childhood, are but one factor in melanoma – genetics and diet are more important.  The Vitamin D Newsletter, August 2006

So, bottom line:

-judicious amounts of mid-day sun is best for natural Vitamin D

-avoid tanning beds

-use sunblock if your recreation involves longer amounts of mid-day sun

-get your Vitamin D level checked and optimize levels with either natural sun or oral supplementation, aim for a level of 50-70

-follow the advice on diet outlined by Dr. Cannell (above)