Vitamin-D levels in exclusively breast fed infants less than six months of age: Do they need supplementation?

Introduction: There is growing interest in subclinical vitamin D deficiency for the non-skeletal health benefits. There is good evidence that breastfed babies not supplemented with vitamin D have low vitamin D concentration and are at risk of rickets.

Hypothesis: Exclusively breastfed babies often have low levels of vitamin D and are at risk of having rickets if not supplemented with vitamin D.

Objective: Measurement of serum 25(OH) D levels in exclusively breastfed babies.

Method: It was an observational, cross sectional study. Thirty healthy infants less than 6 months of age, on exclusive breast feeding and not on any vitamin supplementation were randomly selected. Vitamin D, serum calcium, phosphorus and alkaline phosphatase levels were measured in all these babies and those with clinical features of rickets were subjected for x-ray evaluation.

Results: Twenty eight (93.3%) had hypovitaminosis D (value <20ng/ml) including severe deficiency (<5ng/ml) in two babies (6.7%). The mean value of vitamin D level was 8.871± 4.78ng/ml. The mean ionic calcium value was 5.07± 0.67 and the mean inorganic phosphorus value was 6.25±1.18 mg/dl, which were normal for this age group. The alkaline phosphatase level was uniformly elevated with 28 (93.3%) babies having values >420U/L. There was no statistically significant relationship between vitamin D levels and the birth weight or nutritional status of the infant. Radiological changes were found in three (10%) babies.

Conclusion: Vitamin D deficiency is highly prevalent in exclusively breastfed healthy infants and hence vitamin D should be supplemented.

Sri Lanka Journal of Child Health, 2014; 43(2): 92-96

(Key words: Exclusively breastfed infants; vitamin D deficiency; subclinical rickets)

DOI: http://dx.doi.org/10.4038/sljch.v43i2.7010