However, further studies have indicated that vitamin D deficiency can contribute to a long list of other ailments, many more than previously thought. Evidence has emerged that suggests links between insufficient levels of vitamin D and autoimmune illnesses, chronic pain, cancer, depression, diabetes, neuromuscular disorders, autism, heart disease, high blood pressure, hyperthyroidism, and many others. Vitamin D deficiency has been shown to severely weaken the immune system, factoring in the spread of viral illnesses like influenza and the common cold.
Most vitamin D in the body is produced by exposure to sunlight. Many people, heeding warnings by health care professionals about skin cancer prevention, are restricting their exposure to the sun with the use of sunscreen or by remaining indoors. This trend has made maintaining an adequate level of vitamin D in the system difficult, resulting in deficient levels in approximately 40% of adults. Deficiency rates are highest among people of color, as skin pigmentation blocks a portion of the ultraviolet light to which it is exposed, but is a prevalent problem in all segments of the population.
While preventing skin cancer is certainly important, evidence is mounting that a moderate amount of sun exposure is critical to good health, and supplements may be wise in the winter months when sunlight is weakest. Some experts suggest that just an hour of sunshine a day can be enough to prevent deficiency in the summer months.
There is a lot more information on the subject available, with some of the articles and studies I found most interesting and informative linked in the text....but be sure to step away from the screen for a few minutes to enjoy a bit of sunshine, guilt free...