The Role of Sunlight Exposure in Reducti

General Information

Editorial

Haider Abdul-Lateef Mousa, MB ChB, MSc

Lecturer, College of Medicine, University of Basrah, Iraq

Corresponding author

Dr. Haider Abdul-Lateef Mousa, MB ChB, Msc, Lecturer, College of Medicine, University of Barsah, PO Box 601, Post Code 42001, Ashar, Basrah, Iraq, E-Mail: haideramousa@hotmail.com; haideramousa@gmail.com

Received Date: 19^th March 2015

Accepted Date: 20^th March 2015

Published Date: 23^rd March 2015

Citation

Mousa HA (2015) The Role of Sunlight Exposure in Reduction of Cardiovascular Diseases. Enliven: Clin Dermatol 1(1): e002.

Copyright

@ 2015 Dr. Haider Abdul-Lateef Mousa. This is an Open Access article published and 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.

Cholesterol is a precursor to vitamin D. Since sunlight is required to turn cholesterol into vitamin D, avoiding the sun will likewise undermine our ability to synthesize vitamin D.

Keywords

Vitamin D; Sunlight; UV light; Cardiovascular diseases prevention; Cholesterol

Cholesterol is a precursor to vitamin D. Since sunlight is required to turn cholesterol into vitamin D, avoiding the sun will likewise undermine our ability to synthesize vitamin D.

Vitamin D deficiency has been associated with the prevalence of cardiovascular disease (CVD), suggesting that vitamin D does not participate solely in â??classicalâ?Â calcium metabolism in bone, the intestines, and the kidney. Both the consumption of vitamin D from foods containing and/or fortified with vitamin D₃ (cholecalciferol) and sun light exposure increases vitamin D in the body [1,2]. Synthesis of vitamin D starts in the skin as a non-enzymatic process, which begins during sunlight exposure, when the absorption of ultraviolet B radiation results in transformation of 7-dehydrocholesterol, a metabolite of cholesterol that is stored in the skin, to precholecalciferol (previtamin-D₃) that is immediately converted into cholecalciferol (vitamin D₃). Then cholecalciferol is transported to the liver where it undergoes hydroxylation, which results in formation of calcidiol or 25-hydroxyvitamin D (25(OH)D₃). The second metabolic process takes place in the kidney, where calcidiol undergoes hydroxylation at the C-1 position to the hormonal, resulting in the most active metabolite known as 1,25-dihydroxyvitamin D (calcitriol) [3]. Serum 25(OH)D₃ (calcidiol) is the major storage form of vitamin D that its serum level is a clinical indicator of overall vitamin D3 status. [4]. Previous studies in Caucasians have shown that serum levels of 25(OH)D₃ were inversely related to hypertension, diabetes, carotid atherosclerosis, myocardial infarction, congestive heart failure, stroke, microalbuminurea, and kidney dysfunction. However, neither the role of vitamin D deficiency in the development of CVD nor the practical recommendation for its supplementation to prevent CVD has been established [5]. Many previous studies have found that vitamin D deficiency is an independent risk factor for cardiovascular disease [5-7] and type 2 diabetes [8]. Although, one study revealed arteriotoxicity evidence of vitamin D, and there was an elevated level of serum 25-hydroxyvitamin D3 in patients with ischemic heart disease [9]. It has been confirmed that cholesterol level increased during winter months. Furthermore, there was evidence that cholesterol level diminished by outdoor activity [10]. Investigators in South Africa performed a study on black and white teachers. They have found that blacks demonstrated a substantially higher prevalence of CVD compared to whites [11].

Conclusion

Sunlight exposure with consumption of cholesterol for vitamin D synthesis might be the protective factor from CVD. Therefore, vitamin D supplement is questionable in regard to CVD prevention. This could also explain the higher rate of CVD among people with dark skin who live in cold climate countries where the effect of reduced sunlight exposure is more prominent. Therefore, the prevalence of cardiovascular diseases according to in-door and out-door occupation might be different. The average duration of sunlight exposure could have an effect on cholesterol level.