Review of vitamin D deficiency among breast-feeding infants

Abstract

Background Vitamin D deficiency is prevalent in many places across the world. Breastfeeding has been suggested to be a significant predictor of vitamin D deficiency during infancy, which is preventable through proper supplementation. However, whether Hong Kong should adopt the international recommendation for supplementation of exclusive breastfed infants is still not yet answered.

Objective: To review the available evidence regarding the association between breastfeeding and vitamin D deficiency during infancy, as well as the effectiveness of vitamin D supplementation of breastfed infants as an intervention measure.

Methods A total of 5112 potentially relevant articles were searched and identified from MEDLINE (OVID, Pubmed), Science Citation Index Expanded (ISI Web of Science), Cochrane Central Register of Controlled Trials, EMBASE, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Chinese database (CNKI) without restriction from inception to July-06-2012. 5065 articles were excluded after the initial scanning of title and abstracts. 36 were subsequently excluded due to methodological issues. A total of 11 studies were included and reviewed by two independent reviewers.

Results This review pooled together a total of 1126 exclusively breast-fed infants for less than one year old from 11 studies. The pooled average prevalence of vitamin D deficiency was 54.2%. The association between breastfeeding and vitamin D deficiency during infancy has been reported consistently, and it was found to be one of the strongest predictors of vitamin D deficiency for infants less than one year old. Sunlight exposure, season, and skin pigmentation were also found to be important affecting factors. Supplementation to breastfed infants with the dosages as recommended by American Academy of Pediatrics (AAP) seem to be effective in lifting up the vitamin D levels.

Conclusions The Hong Kong Government and relevant health sectors should conduct local epidemiological study to investigate the problem of concern among our breast-fed infants, and seriously consider or evaluate the AAP recommendation of supplementation.