An overwhelming number of individuals are chronically deficient in Vitamin D, and in winter our levels of this “sunshine vitamin” tend to drop even further. This is concerning because Vitamin D levels relate to such a wide number of illnesses and heath parameters. The main role of Vitamin D in the body is to regulate levels of calcium and phosphorus with respect to building and repairing bone and is strongly associated with bone health. However, low levels of Vitamin D are also associated with the occurrence of many health problems worldwide, including cancers, cardiovascular disease, immune deficiency, mental illness and cognitive decline.
Vitamin D is synthesized in the skin after UVB exposure, further metabolized in the liver and converted to its active form in the kidney. Because Vitamin D is not commonly found in most foods, it may be tempting to spend more time in the sun to increase Vitamin D levels, but this has not been found to be reliable. Low levels of Vitamin D are found in all populations and in all climates, including those experiencing bright sunlight most of the year, as well as in individuals who avoid sun exposure and those who use sunscreens. Unfortunately, the UVB rays that trigger Vitamin D synthesis are also related to increased risk of actinic keratoses, squamous cell carcinoma, and basal cell carcinoma. The good news is that epidemiologic population studies in the United States, Europe and Canada have demonstrated that supplementing with even 1000-2000 IU of Vitamin D daily can significantly lower risk of malignancy and other health problems.
The safest suggestion is to always use a high-quality SPF like Extreme Protect SPF 30 or Eclipse SPF 50+ to protect against skin cancer and photoaging, and to see your doctor to determine your personal Vitamin D levels and consult regarding any additional Vitamin D supplement recommendations.