Children treated with a dairy-free diet are in a group of those at risk of nutritional deficiencies, including vitamin D deficiency.THE AIM of this study was to evaluate the vitamin D status in children with cow's milk allergy (CMA) treated with a dairy-free diet.
Material and methods: The study involved 66 children with CMA, aged 2-5 years (mean age 3.9±1.9 yrs). The children were treated with a milk-free diet (high degree of protein hydrolysates or soy formulas/soy products) and remained under the care of the medical and nutritional team. The majority of the children lived in urban areas and their parents have mainly secondary or higher education. The supply of vitamin D in children's daily food rations was evaluated and related to Adequate Intake (AI) as well as the recommendations contained in the Medical Standard (2009) for the prophylaxis of vitamin D deficiency. Fifteen (22.7%) children in the autumn-winter season used vitamin D containing supplements. The serum 25-hydroxyvitamin D [25(OH)D] concentration was measured and related to the recommended levels from Medical Standard (2009). Taking into consideration the possibility of seasonal differences in vitamin D status, blood samples for the 25(OH)D assay were collected from April to September (spring-summer season) in 34 (51.5%) children and from October to March (autumn-winter season) in 32 (48.5%) children.
Results: The mean supply of vitamin D in the diets of the children with CMA was 5.9±3.7 μg/d. The mean supply of vitamin D in supplements in the group of children receiving them was 143.6±132.9 IU/d [3.6±3.3 μg/d]. The mean 25 (OH)D serum concentration among the children without taking into account the season for blood withdrawal was 28.7±9.9 ng/ml. Taking into account the season of blood sample collection, the mean 25(OH)D serum concentration in children in spring-summer was 30.1±7.8 ng/ml, while in autumn-winter 27.5±11.2 ng/ml, p>0,05. A positive correlation between the supply of vitamin D in the children's diets and 25(OH)D serum concentration (Spearman correlation coefficient r=0.46, p<0,01) was found. The mean supply of vitamin D in the children's diets and the mean 25(OH)D serum concentration did not differ significantly depending on the place of living and the parents' education.
Conclusions: 1. Vitamin D supplied by the diets of the children with CMA remaining under our care was compliant with the Adequate Intake, but lower than the recommendations contained in the Medical Standard. 2. The serum 25(OH) D concentration in these children in the spring-summer as well as autumn-winter season indicated the optimal vitamin D status. 3. Being under constant medical and nutritional care is one of the conditions for an appropriate vitamin D supply in children with CMA.