Don’t be kept in the dark – sunlight avoidance can damage your health. Our Sun emits a range of intense electromagnetic radiations, a portion of which is visible to us as light and another that we experience as heat.  Other frequencies of the Sun’s emissions are not tangible to us but we know that at least one, ultraviolet radiation (invisible light), is essential for our health. The Earth cloaks itself in a dynamic electromagnetic force field that provides some protection from the Sun’s radiations, without which Earth would be as lifeless as our Moon.  While life has been able to evolve within this protective field it has also had to equip itself with further protection from the effects of those radiations that do penetrate this field.  For many animals on land this has meant the evolution of fur, hair and feathers to protect their skin from ultraviolet radiation and to help regulate body temperature in higher and lower temperature regions. Because humans have largely lost their hair during recent evolution this has meant the concurrent development of protective cellular mechanisms to compensate for the absence of any skin covering, such as the use of special cells that filter out harmful radiations by producing a brown pigment called melanin.  At the same time we have made use of ultraviolet radiation to generate vitamin D within our skin - a nutrient essential for our survival. These cellular mechanisms have been extensively studied and we now know some important facts about them.  The most important is that to be healthy humans need appropriate, adequate sunlight exposure throughout the year for the production of vitamin D in the skin to supplement dietary intake, which is generally inadequate to satisfy metabolic needs.  At the same time we need to acquire from the diet adequate levels of all the essential nutrients required to produce the pigments and the enzymes that help maintain the integrity of these cells. It is has also been discovered (as long ago as the turn of the 20^th century) that appropriate levels of sunlight have a stimulating affect on the brain and its chemistry and can be utilized to help protect the skin (and domestic and hospital environments) from harmful microorganisms.  Appropriate sunlight exposure can also be used to stimulate healing, both of the skin and the rest of the physiology. Sunlight deprivation has been established as a major contributing factor in the progression of a number of life-threatening diseases, as well as seasonal and other forms of depression. These conditions levy a heavy cost on the resources of societies by increasing the overall need for medical interventions, coupled with the distress and the loss of working time and social function associated with depression and other mood disorders. Inadequate sunlight exposure is the norm in Western cultures, especially in the higher latitudes of the northern hemisphere where large proportions of the Western population live.  Ensuring appropriate sunlight exposure is central to maintaining balanced health and resistance to disease, both by the provision of vitamin D (a pro-hormone) and the stimulation of serotonin levels in the brain.  These two hormones can also be repleted, according to individual need, by improving dietary sources and by the provision of nutritional supplements. Back to Top Back to Introduction