Vitamin D3 deficiencies in children and adults – how to diagnose and treat

Vitamin D, which was mostly associated with maintaining a calcium-phosphate balance, has a pleiotropic effect and regulates many important processes in our body. Cross-sectional studies involving a group of 5775 Polish people conducted by Płudowski et al. showed that 89.9% of respondents had vitamin a D level that was too low. It is also estimated that approx. 50% of the human population has insufficient vitamin D concentration. Vitamin D deficiency is diagnosed based on 25-hydroxycholecalciferol serum concentration measurement. In 2018, the “Frontiers in Endocrinology” journal published a vitamin D supplementation guide created by the Polish Society of Paediatric Endocrinology and Diabetes and the expert panel with national consultants and representatives of scientific societies. These recommendations specify supplementation doses for particular social groups of the general population and high-risk groups, and define the protocol of supplementation based on 25-hydroxycholecalciferol levels. The daily recommendations for the general population with normal body weight are as follows: newborns and infants up to 6 months: 400 IU, infants from 6 to 12 months: 400–600 IU, children from 1 to 10 years old: 600–1000 IU, children from 11 to 18 years old: 800–2000 IU, adults from 19 to 75 years old: 800–2000 IU, and people over 75 years old: 2000–4000 IU. The dosage range depends on body weight and additional factors.