Recent studies show that 20 minutes of sun exposure per day is ideal for optimum health—it’s like taking a daily dose of vitamin D.  However, during the past few decades, incidents of skin cancer have steadily been on the rise.  Some experts blame this on damaging ultraviolet rays, which have intensified over the past several years due to global warming.  In addition, popular pharmaceutical drugs like antibiotics, antidepressants, diuretics and retinoids are known to cause increased sun sensitivity.  As such, it’s critical to apply UV protection before heading outdoors.