Vitamin D is an essential nutrient for bone formation during childhood. It helps support healthy bone mineralization and calcium homeostasis regulation. It also helps promote healthy immune system development, cellular growth, and cardiovascular health. Recent research highlights the critical role of vitamin D in pediatric health.  

Deficiencies and insufficiencies in vitamin D are common in pediatric and adult populations. In the pediatric population, vitamin D deficiencies may be a result of inadequate nutritional intake, decreased absorption, certain pathologies, lifestyle changes, lack of sun exposure, and genetic conditions. Other factors that may contribute to vitamin D deficiencies include living in higher latitudes and areas with restricted sun exposure, and individuals with darker skin pigmentation. A review article published by Castano and colleagues explored recent literature on the impact of vitamin D deficiency on bone health in the pediatric population. 

Rickets is a condition associated with deficiencies in the mineralization of bone and cartilage, skeletal deformities, and growth failure. The development of nutritional rickets has been associated with deficiencies in vitamin D in children. Despite efforts to fortify certain foods and milk with vitamin D, incidences of rickets have globally increased.  

Castano and colleagues highlight certain risk factors for the development of rickets. These include certain genetic changes in vitamin D receptors (VDRs) and other single nucleotide polymorphisms (SNPs). The results from twin studies evaluating the inherited vitamin D status varies widely between 20% and 85%. More research is needed before conclusions can be made.  

Certain chronic illnesses may also contribute to nutritional rickets, according to Castano and colleagues. Inflammatory bowel disease (IBD) in children may contribute to malabsorption problems. Chronic liver disease may cause altered synthesis and absorption impairments. Kidney diseases and other pathologies, such as cystic fibrosis may also be associated with vitamin D deficiencies.  

Vitamin D helps support both innate and adaptive immune health. VDRs are present on certain immune cells, including lymphocytes and monocytes. Vitamin D has been shown to modulate antimicrobial peptide transcription, the secretion of interleukin (IL)-10, and the production of certain pro-inflammatory cytokines in monocytes and macrophages through VDR signaling. The VDR signaling in dendritic cells has also been associated with certain aspects of T-cell differentiation. 

Vitamin D status has been associated with the incidence of microbial illness in the pediatric population. A population study reported that newborns with lower levels of serum vitamin D had a greater prevalence of otitis media and upper respiratory infections at 3 months of age and wheezing at 15 months. A randomized control trial explored the potential role of supplementation with vitamin D in more than 300 children during the winter months to help prevent influenza A. The treatment arm was shown to have a 58% lower likelihood of contracting influenza A as compared to a placebo. 

Vitamin D supports healthy bones and normal growth. It also helps support the development of a healthy immune system.  

By Colleen Ambrose, ND, MAT