The Role of Outdoor Exposure and Vitamin D?
Many people in our society today do not spend enough time outside which could lead to low levels of vitamin D. Certain studies have shown that approximately 36% of healthy adults and up to 57% of inpatients in the US have an inadequate amount of vitamin D (1). This goes to show how a little sunlight can go a long way in regards to our health and wellness. In fact, ten minutes a day of outdoor exposure is thought to be enough to prevent vitamin D deficiencies. Still many people could be suffering from a vitamin D deficiency, and there are some serious health concerns associated with it. Supplemental doses of vitamin D and sensible sun exposure could prevent deficiency in most of the general population.
In the past vitamin d deficiency was associated with bone disease because it is essential for efficient utilization of dietary calcium. If there is an inadequate amount of vitamin D the amount of calcium absorbed will not be enough to satisfy your body’s calcium requirement. Another important function of vitamin D is for muscles function. Any type of deficiency will cause muscle weakness and muscle aches and pains in both children and adults. This could lead to an increase in musculoskeletal injuries associated with falls. Recently, researchers have suggested that low levels of vitamin D are also linked with anything from cardiovascular disease to neurological ailments. According to researchers at the University of Texas Southwestern Medical Center they have even gone as far relating low levels of vitamin D to depression. (2)
It is safe to assume that with all the advances in modern medicine a vitamin D deficiency should be a health concern in the United States. Many believe the elderly population has the most risk, but today’s youth could also be at risk as well. With the advances in technology many children do not play outside as frequently and therefore lack exposure to sun’s ultra violet rays which provide our bodies the main source of vitamin D. It has been estimated that 90% or more of our required vitamin D comes from exposure to sunlight. Anything that interferes with our skins ability to absorb the solar ultraviolet radiation, such as increased melanin pigmentation and sunscreen use, will diminish the cutaneous production of vitamin D (3)
Many health professional have expressed concern about direct sunlight exposure to the skin and therefore prescribe sunscreen when outside. Application of a sunscreen with sun protection factor 8 reduces the capacity of the skin to produce vitamin D by 95%. So this could be misguided information which could have serious profound consequences on our overall health. The risk associated with low levels of vitamin D has shown to have a correlation of chronic disease and therefore some exposure to the sun would be very beneficial. There is little evidence that adequate sun exposure will substantially increase the risk of skin cancer; rather, long-term excessive exposure and repeated sunburns are associated with certain skin cancers.
The most cost-effective and efficient method for preventing vitamin D deficiency is to have adequate exposure to sunlight. Therefore it is recommended to have vitamin D checked once a year, preferably at the end of the fall season to ensure that you do not become vitamin D- deficient before winter when typically outdoor exposure frequency tends to diminish. Prevention of vitamin D deficiency not only preserves bone and muscle health but also may help prevent many chronic diseases and preserve overall health and well-being. So get out more and enjoy the sun!
(1)Michael F. Holick, High Prevalence of Vitamin D Inadequacy and Implications for Health. Mayo Clinic Proceedings. Volume 81, Issue 3 , Pages 353-373, March 2006 (2) DeFina, Willis, Leonard, Weiner, Brown. Association Between Low Serum 25-Hydroxyvitamin D and Depression in a Large Sample of Healthy Adults: The Cooper Center Longitudinal Study. Mayo Clinic Proceedings. Volume 86, Issue 11 , Pages 1050-1055, November 2011
(3) Holick MF . Vitamin D: a millenium perspective . J Cell Biochem . 2003;88:296–307
(4) Khosla S . Minireview: the OPG/RANKL/RANK system . Endocrinology . 2001;142:5050–5055