Vitamin D status in infants depends on supplementation. We examined the vitamin D status in relation to supplementation dose and scheme in infants.
One hundred thirty-four infants age 6 months and 98 infants age 12 months (drop out 27%) were investigated. Vitamin D intake (diet, supplements), anthropometry, and 25-hydroxyvitamin D (25-OHD) serum concentration at the 6th and 12th months were assessed.
Vitamin D intake of 1062 ± 694 IU at the 6th month was not different from that at the 12th month (937 ± 618 IU). Vitamin D intake expressed in international units per kilogram of body weight decreased from 141 ± 80 IU/kg at the 6th month to 93 ± 62 IU/kg at the 12th month (P < 0.0001), which was associated with a reduction in 25-OHD from 43 ± 20 ng/mL to 29 ± 12 ng/mL, respectively (P < 0.0001). In the subgroup of everyday supplemented infants (n = 43), vitamin D intake decreased from 143 ± 88 IU/kg at the 6th month to 118 ± 60 IU/kg at the 12th month (P < 0.05), which coincided with a reduction of 25-OHD from 40 ± 19 ng/mL to 32 ± 13 ng/mL (P < 0.01). In the subgroup with variable supplementation habits (n = 32), vitamin D intake decreased from 146 ± 79 IU/kg to 77 ± 56 IU/kg (P < 0.001), which was associated with a reduction of 25-OHD from 42 ± 21 ng/mL to 25 ± 8 ng/mL (P < 0.0001). 25-OHD concentration change between the 6th and the 12th months negatively correlated with the 25-OHD level assessed at the 6th month (r = −0.82; P < 0.0001).
Vitamin D supplementation of infants should consider their rapid body weight increment. We postulate vitamin D daily dose close to 100 IU/kg body weight as favorable for infants up to age 12 months.
*Department of Biochemistry and Experimental Medicine, Poland
†Department of Gastroenterology, Hepatology and Immunology, Children's Memorial Health Institute, Aleja Dzieci Polskich, Poland
‡Department of Biochemistry and Clinical Chemistry, Warsaw Medical University, Banacha Warsaw, Poland
§Department of Pediatrics and Auxiology, “Dr. L.Zamenhof” University Children's Hospital, Medical University of Bialystok, ul. Waszyngtona, Bialystok, Poland.
Received 3 September, 2010
Accepted 20 February, 2011
Address correspondence and reprint requests to Pawel Pludowski, Department of Biochemistry and Experimental Medicine, Children's Memorial Health Institute, Aleja Dzieci Polskich 20, 04–730, Warsaw, Poland (e-mail: firstname.lastname@example.org).
The study was a part of a research project “Nutritional Habits and Nutritional Status in Polish Infants,” funded by a Gerber Academy Scientific Grant.
The authors report no conflicts of interest.