Endocrine Abstracts

In line with European guidelines, infant formulas in France have been vitamin D-fortified with a vitamin D3 content of ~400 IU/l. New guidelines for the prevention of vitamin D deficiency and rickets have subsequently been published and the vitamin D supplement for formula-fed infants was reduced from 800 to 400 IU per day.

To contribute to the evaluation of the need for vitamin D supplementation, a study was conducted to assess vitamin D3 intake (cholecalciferol) provided by sunlight exposure and fortified milk, and intake provided by supplementation prescribed in form D2 ergocalciferol.

This study was conducted in a population of Caucasian infants.

The vitamin D2 intake, the type and quantity of milk received, time spent outdoors and clothing modalities were recorded.

Vitamin D status was assessed on serum left over from a blood sample obtained during the infant’s hospitalization; 25(OH)D2 and 25(OH)D3 levels were evaluated by HPLC followed by radioimmunoassay.

Forty-five term infants between the ages of 2 and 14 months (26 boys and 19 girls) were included, during Winter for 19 cases and during Summer for 26 cases.

The contribution of 25(OH)D2 vitamin D supplementation (mean: 18 ng/ml; range: 2–47) was approximately equal to vitamin D intake from sun exposure and 25(OH)D3-fortified milk (mean: 21 ng/ml; range: 5.5–32).

Three infants had a low 25(OH)D₂ level and one had a level of 2 ng/ml. The 25(OH)D₃ level was low (<10 ng/ml) for 5/36 infants, all included during Summer.

The most original result of this study is the equivalent contribution to the infant’s vitamin D status of D₃-intake by fortified milk and sun exposure and D₂-intake by the prescribed vitamin D supplement. The vitamin D status appeared to be satisfactory under these conditions, with extreme values within the locally defined normal range.