22 November 2013
A new US study reports that low blood vitamin D levels seem to increase the risk of red blood cell deficiency in healthy children.
In the observational study, the concentrations of vitamin D and hemoglobin were measured in the blood samples of 10,410 apparently healthy children and adolescents, aged 1 to 21 years (1). The study results showed that vitamin D levels were consistently lower in children with low hemoglobin levels compared with non-anemic children. Children with mild vitamin D deficiency (levels below 30 nanograms per milliliter) had nearly twice the risk of anemia compared with those who had normal vitamin D levels. Black children had higher rates of anemia compared with white children (14% vs. 2%) and had considerably lower vitamin D levels overall, but their risk of anemia did not increase until their vitamin D levels dropped far lower than those of white children.
The researchers commented that these results are not proof of cause and effect, but rather evidence of a complex interplay between low vitamin D levels and hemoglobin (the oxygen-binding protein in red blood cells). If the findings are confirmed through further research, low vitamin D levels may turn out to be a readily modifiable risk factor for anemia that can be easily treated with supplements. The racial variance seen in the study shows that a pathologically low vitamin D level in some may appear to be adequate in others. This would raise questions about the current one-size-fits-all approach to treatment and supple- mentation.
Anemia, which occurs when the body does not have enough oxygen-carrying red blood cells, is believed to affect one in five children at some point in their lives. Several large scale studies have found severe vitamin D deficiency (at or below 20 ng/ml) in about one-tenth of US children, while nearly 70% have suboptimal levels. Untreated chronic anemia and vitamin D deficiency can have wide-ranging health consequences, including organ damage, skeletal deformities and frequent fractures, and lead to premature osteoporosis in later life. Several mechanisms could account for the link between vitamin D and anemia, including vitamin D's effects on red blood cell production in bone marrow, as well as its ability to regulate immune inflam- mation, a known catalyst of anemia.
15 August 2014
While human milk is the preferred source of most nutrients for infants during the first year, there has been concern about the adequacy of human milk in providing vitamin D.
3 November 2011
Increased intakes of B vitamins may slow cognitive decline in people with mild cognitive impairment, suggests a new UK study.
1 August 2011
At a recent conference 13 experts from different areas, including basic science, medicine and epidemiology, came together to define the term ‘evidence-based nutrition’ as it relates to the substantiation of health claims.
