Reference values of vitamin D status: Why is everything not so clear

Abstract

Vitamin D plays an important role in maintaining human health and has many positive properties. Its deficiency can negatively affect the body and worsen the quality of life. Worldwide, deficiency of this vitamin is a widespread problem. Different states set their own reference values of vitamin D levels for their populations. The article considers the justifications underlying the establishment of recommendations for its level and the basic units of measurement of 25(OH)D. Understanding the differences in normal vitamin D values between countries makes it possible to more accurately adapt recommendations to specific populations and ensure that optimal vitamin D levels are achieved, which is necessary to maintain the health of the population.