Mother Nature created SHADE for a reason.

Robert E. Martin (“Pedigreed RATS yield key to New Secrets of Health,” Popular Science, Mar. 1932) wrote …

“One of the many peculiar discoveries made at the Washington laboratories concerns food irradiated with ultra-violet light. Sometimes, the tests showed, the rays stored up vitamin D, and at other times the rats continued to develop the symptoms of rickets after the food so treated was given them. Finally tests indicated that when the rays bombarded the food for too long a period they actually destroyed the vitamins which at first they had stored up.”

“What appears to be a limitation in the clinical value of ultraviolet radiation as an agent for therapeutic good, seems to turn out actually to be its special feature – the inability to penetrate greater than skin depths. By thus limiting the depth to which ultraviolet radiation may penetrate the body, this energy becomes specifically sensitive in its ability to stimulate the sympathetic nervous system to the exclusion of the parasympathetic nervous system. Translated into the language of the clinic, this speciality of action is revealed in the property of ultraviolet which, of all cosmic forces, appears to be the one selected to preside over calcium metabolism.”