Vitamin D Deficiency- Main Factors Affecting The Serum 25-Hydroxyvitamin D ([25(Oh)D]) Status And Treatment Options. Zehra Edis & Samir Haj Bloukh

Abstract

Vitamin D deficiency (VDD) is already recognized as a pandemic affecting over 1 billion people worldwide. The scientific debate about VDD and its complications is far from resolved because of lack of scientific based proofs in certain areas. Most observational and epidemiological trials, as well as meta-analyses report the benefits of optimal serum 25-Hydroxyvitamin D ([25(OH)D]) status. Furthermore important randomized controlled trials (RCTs) give in many cases conflicting results due to certain limitations. Moreover the debate continues whether hypovitaminosis D is cause, result or by-product of poor health. Another approach is the resilience factor hypothesis, which describes serum vitamin D status as helpful in survival of fatal conditions and therefore inversely correlated to morbidity and mortality. Endogenous and exogenous vitamin D synthesis are associated to environmental, biological and social (economical and cultural) factors. Mainly VDD is a consequence of the modern lifestyle including urbanization, indoor dwelling with work- or entertainment-based lower mobility in general population and partly profit- and mass-production-oriented farming methods resulting in products with lower vitamin D content. A healthy lifestyle with physical activity, adequate and sensible sun exposure and intake of quality nutrients, including those rich in natural vitamin D will ensure optimal serum Vitamin D concentrations.
Key words: Vitamin D; sunlight; lifestyle; age; gender; socio-economic status; adequate intake; fortification; supplementation; recommendations