Written By Kassie the ecoPharmacist. On Feb 01. In Health and Wellness

Vitamin D deficiency is the most common nutritional deficiency worldwide. In the US and Europe, more than 40% of the adult population over 50 years of age is vitamin D-deficient, but this condition goes largely undiagnosed, as most patients are asymptomatic. Main causes include sun avoidance, using sun protection, increased skin pigmentation, inadequate dietary and supplemental vitamin D intake, malabsorption syndromes, obesity, and medication use. The most severe forms of deficiency are more common with acquired and inherited causes, and include growth retardation and rickets in children and osteomalacia, osteopenia, and osteoporosis in adults. To maximize vitamin D effects on the skeleton and on calcium metabolism, serum 25-hydroxyvitamin D levels should be over 30 ng/mL; deficiency is defined as a level under 20 ng/mL, and insufficiency is defined as 21 – 29 ng/mL. Both deficiency and insufficiency are corrected by giving vitamin D3 in treatment doses followed by lifelong maintenance doses; adequate sensible sunlight exposure should be encouraged. Additional replacement with 1,25-dihydroxyvitamin D or one of its active analogs is necessary for those with disorders of vitamin D metabolism.