14 DAY TRIAL // According to a new study carried out by investigators at the University of Michigan School of Public Health and the Michigan State University, it would appear that children who suffer from vitamin A deficiency are more likely to become ill than their peers, and also tend to get sick more often.
The researchers uncovered that vitamin A deficiencies led to a higher incidence of gastrointestinal and respiratory conditions in school-aged children. The study was carried out on 2,800 kids aged 5 to 12, all from Bogota, Columbia. Test participants were followed for an entire year.
The team focused on a type of vitamin A called retinol. Scientists regularly measured retinol amounts in each test subject, and then quantified individual risks of developing an illness over the following 12 months. The most common conditions were diarrhea with vomiting and cough with fever.
This is one of the few studies to investigate the effects of insufficient vitamin A amounts in children of this age. Most other researches were focused on kids younger than 5, since this interval is thought to be critical for an individual's development later on in life.
Details of the new investigation were published in a recent online issue of the Journal of Nutrition. The senior author of the study was U-M associate professor of epidemiology, Dr. Eduardo Villamor.
“Studies of older children have included a range of micronutrients administered together, but no study had estimated the potential role of vitamin A alone in this age group. The association we found with vitamin A followed a dose-response pattern, in that higher blood concentrations of retinol were related to fewer symptoms,” the investigator explains.
The team also analyzed the connections between other micronutrients – such as iron, folate, zinc, and vitamin B12 – and gastrointestinal and respiratory illnesses, but only vitamin A was found to produce a direct causal effect.
“As we have learned from vitamin A supplementation to younger children, which has shown mixed success in preventing illness, the picture is more complicated than it might appear,” Villamor concludes.