Low vitamin D linked to anaemia

Children with low levels of vitamin D may have an increased risk of anaemia, in which the body has too few oxygen-carrying red blood cells, U.S. researchers say. Lead investigator Dr. Meredith Atkinson, a pediatric nephrologist at The Johns Hopkins Children's Center, and colleagues examined the relationship between hemoglobin - how anemia is measured - and vitamin D, by looking at data from the blood samples of more than 9,400 children, ages 2-18. The study found the lower the vitamin D levels, the lower the hemoglobin - the number of oxygen-carrying red blood cells - and the higher the risk for anaemia. Children with levels below 20 nanograms per milliliter of blood had a 50 percent higher risk for anaemia than children with levels 20 ng/ml and above. For each 1 ng/ml increase in vitamin D, anaemia risk dropped by 3 percent, the researchers say. In addition, the findings, presented at the annual meeting of the Pediatric Academic Societies in Denver, indicated only 1 percent of white children had anaemia, compared with 9 percent of black children. Researchers have long known that anemia is more common among black children but the reasons remain unclear. The study suggests low vitamin D levels in black children may be an important contributor to anaemia. "The striking difference between black and white children in vitamin D levels and hemoglobin gives us an interesting clue that definitely calls for a further study," Atkinson says in a statement.