A UCC study of more than 1,000 newborns found almost half (46%) were deficient in vitamin D, rising to 62% in wintertime.
The deficiency can cause rickets, a softening of the bones, that can lead to skeletal deformities. However, when researchers followed up with the babies, there was no sign of rickets.
Lead author Mairead Kiely said this was “in all probability” down to the diligence of mums complying with the national supplementation policy during the first year of an infant’s life. HSE policy is that all infants, whether breastfed or formula fed, be given a daily supplement of the vitamin.
Prof Kiely, principal investigator of the maternal and child nutrition research programme at Infant, said if the deficiency had not been corrected through adherence to this policy, “in all likelihood, some children would have been at risk” of poor bone health.
The co-director of the Cork Centre for Vitamin D and Nutrition Research said babies most at risk were those who were vitamin D deficient from birth, where it was not corrected and who were calcium deficient as well. Such cases were “very rare” in Ireland.
At a lower level of risk, were newborns who were vitamin D deficient which was not corrected by use of supplements or where the baby continued to be breastfed after six months, instead of being weaned on to solids. “If they are not weaned on to solid food until eight months, the baby is at risk of iron deficiency which can cause growth failure.”
She said occasionally mothers put their babies on a vegan or macrobiotic diet, and this was not appropriate.
Prof Kiely said that, while there are national supplement policies and infant food guidelines for the first year of life, and healthy eating guidelines for children aged five upwards, there was “a big gap” for two, three and four-year-olds.
There was also “no policy for mums” — a previous study which Prof Kiely led found one in six mothers-to-be were deficient in the sunshine vitamin.
“If you put policies in place that are clear, parents can make the right decision.”
Prof Kiely is working on providing the evidence to make pregnancy-specific recommendations for vitamin D to prevent deficiency in mothers and babies.
Findings from the study, published in the Journal of Steroid Biochemistry & Molecular Biology, will feed into the EC Odin project which is working to develop solutions to prevent vitamin D deficiency using a food-first approach.
Prof Kiely is a co-ordinator of the Odin project.
© Irish Examiner Ltd. All rights reserved