Pubtexto Publishers | www.pubtexto.com 1 J Community Med Health Res Open Access Journal of Community Medicine and Health Research Volume 1 Issue 2 Review Article Causes, Benefits and Consequences of Vitamin D Deficiency Wimalawansa SJ * Professor of Endocrinology, Cardio metabolic and Endocrine Institute, New Jersey, USA Article Info Article History: Received: 12 November, 2019 Accepted: 19 November, 2019 Published: 25 November, 2019 * Corresponding author: Wimalawansa SJ, Professor of Endocrinology, Metabolism and Nutrition Cardio metabolic and Endocrine Institute, New Jersey, USA; Tel: 732-940-0811; E-mail: suniljw@hotmail.com Abstract Vitamin D deficiency is common worldwide. It is estimated that globally more than 1.5 billion people have vitamin D deficiency and another 1.5 billion have vitamin D insufficiency, which makes this disorder one of the most common nutritional deficiencies in the world. Consequently, it has become not only a pandemic but also an emergency.. Keywords: Hypovitaminosis D, Sunlight, Hypo vitaminosis Copyright: © 2019 Wimalawansa SJ. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction The high prevalence of vitamin D deficiency necessitates affirmative public health actions, including implementation of effective guidelines, advice on safe sun exposure, adequate daily oral supplementation, and vitamin D food fortification. Estimates indicate medical disorders associated with vitamin D deficiency add more than $260 billion annually to the cost of healthcare worldwide, but vitamin D deficiency can be prevented for less than $0.5 billion. Therefore, intervention on a global scale would provide a large benefit for the cost invested. Not only the governments but also employers should make sure that their employees are vitamin D sufficient, allowing them to be healthy and productive. Status of Global Vitamin D Deficiency Vitamin D deficiency is present in significant numbers in most communities and affects all age groups. Despite the presence of abundant sunlight, the incidence of vitamin D deficiency is astonishingly high even among those who live close to the equator, such as in India, Bangladesh, Sri Lanka, and the Far Eastern, Middle Eastern, and Persian Gulf nations [1-4]. Darker skin colour is common among the inhabitants of those regions as an evolutionary engendered protective phenomenon that protects from sunburns and skin cancer but also restricts the generation of pre-vitamin D in the skin. The most common cause of hypovitaminosis D in these countries is sun avoidance behaviors, secondary to the harsh climatic conditions, including the frequent use of umbrellas and cultural habits associated with clothing that covers a great amount of the skin [5,6]. Hypovitaminosis D can be cost-effectively prevented and treated through the combination of adherence to specific public health guidelines and vitamin D supplementation regimens. Why is Vitamin D Important for Humans? Vitamin D deficiency and insufficiency affect all segments of the population worldwide. They are a major problem in women during pregnancy [7]. Because of the relatively shorter half-life in the circulation and the lack of sunlight, deficiency is most prevalent during the winter, in high/low latitudes, in constantly polluted environments, and among people with dark skin [8]. Despite the availability of sunshine, vitamin D deficiency is common in Asia, Northern Africa, the Sub-Saharan region, Latin America, the Caribbean, and Southern Asia [9,10]. Vitamin D is essential for life and musculoskeletal physiology and the proper functioning of the human body. It also has other functions, including coordination of the neuromuscular system, cell growth, modulation of inflammation and immune functions, and prevention of autoimmune diseases [10,11]. In evolutionary terms, when our ancestors started to migrate northward from central Africa, mutation of the melanin gene occurred to produce less skin pigmentation. This allowed individuals to generate optimal quantities of vitamin D [12], which created a natural balance between protecting dermal cells from ultraviolet [UV] damage and avoiding vitamin D toxicity, maximizing vitamin D production in the skin. Synthesis of Vitamin D Vitamin D is both a vitamin and a vital hormone. In humans, more than 80% of the vitamin D requirement is expected to be generated in the skin after exposure to UVB rays in sunlight; however, globally, most people are underexposed to sunlight and ingest too little vitamin D [10]. The use of clothing that covers almost all skin and engaging in certain cultural or religious habits and practices reduce sun exposure. Moreover, UV-protecting creams and ointments also significantly lower the skin penetration of UVB rays; all of these practices increase the risk of hypovitaminosis D. After pre-vitamin D is generated, it