Annales 77.3 - Vitamin D: From Gestation to Adolescence in Health and Disease

Editor(s): Carlos Lifschitz, Jatinder Bhatia, Weili Lin, Andrew Prentice, Frank M. Ruemmele, Hania Szajewska.

Vitamin D is a prohormone absorbed from food sources or supplements and also synthesized in the skin following exposure to ultraviolet light. Few foods naturally contain vitamin D. How much and how frequently do most individuals consume these natural dietary sources of vitamin D? In humans, dermal synthesis is the major natural source of the vitamin. Individuals who do not have sufficient sun exposure, especially infants, require supplemental vitamin D from fortified foods or supplements. Vitamin D deficiency is frequent in all stages of life and leads to serious health problems worldwide. This issue of Annales is dedicated for the discussion of importance of Vitamin D from Pregnancy to Adolescence.

Articles

Vitamin D in Preterm and Full-Term Infants

Author(s): Steven A. Abrams

Vi­tamin D is necessary for the active (transcellular) absorption of calcium and for skeletal health. Inadequate vitamin D in infants leads to increased risks of poor bone mineralization and ultimately rickets. The usual total dietary intake level of vitamin D should be approximately 400 IU daily in healthy infants. Vitamin D is a critical nutrient for bone health and needs to be provided to all infants whether via infant formula or as a supplement to breastfed infants or high dose supplement to their mothers.

Early- Life Effects of Vitamin D: A Focus on Pregnancy and Lactation

Author(s): Carol L. Wagner, Bruce W. Hollis

The active form of vitamin D – 1,25-dihydroxy vitamin D (1,25[OH]2D) – increases during pregnancy and remains elevated throughout, and unlike at other times during the lifecycle, it is directly affected by the circulating 25-hydroxyvitamin D (25[OH]D) concentration. Deficiency of vitamin D appears to affect pregnancy outcomes, yet randomized controlled trials of vitamin D supplementation achieve mixed results depending on when supplementation is initiated during pregnancy, the dose and dosing interval, and the degree of deficiency at the onset of pregnancy. The vitamin D content of mother’s milk is directly related to maternal vitamin D status, and if a woman was deficient during pregnancy, her milk will be deficient unless she is taking higher doses of vitamin D.

Vitamin D in Toddlers, Preschool Children, and Adolescents

Author(s): Sarah N. Taylor

Childhood is a period of significant bone development and, therefore, atten­tion to the vitamin D needed to optimize bone health in child­hood is imperative. Observational studies have pointed to a vitamin D status, as indicated by a 25(OH)D concentration of 50 nmol/L, to ensure avoidance of rickets, and of 75 nmol/L to optimize health. Toddlers and young children are at especially high risk of vitamin D deficiency, particularly those from low-income or immigrant populations and those with underlying diseases (i.e., obesity, cystic fibrosis). These children, especially if not receiving fortified food products, remain at risk for inadequate bone mineralization.