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Year Degree Awarded
Modern Western culture has brought most of us indoors and away from extreme changes in temperature and weather, and perhaps more importantly, away from the sun. Nevertheless, the sun plays a critical role in our survival. Wurtman (1975) has summarized the known and crucial roles played by the sun in human biology. Sunlight acts on the skin to produce vitamin D which is essential for the development of a strong bone structure in children and equally essential for the maintenance of a healthy skeletal structure in the elderly. Sunlight is also known to activate and regulate many biological mechanisms such as the timing of biological clocks, endocrine control, immunologic responsiveness, sexual growth and development, stress and fatigue, and control of colds and infections.