15 May 2024
Iron deficiency risk increases in overweight and obese children
Just because a child looks like they’re getting enough food doesn’t guarantee that they have adequate nutrition.
In children, energy-dense – but nutrient-poor – diets increase the risk of severe health conditions in the future, new research shows.
A new systematic review and meta-analysis, published in BMJ Global Health, shows overweight and obese children have a 51% increase in their risk of iron deficiency compared to children of a normal weight.
“Iron status may be the canary in the coalmine, but the real issue is that prolonged inflammation leads to heart disease, diabetes and fatty liver,” lead researcher Bernadette Moore, professor of nutritional sciences at the University of Leeds, told media.
Eighty-three studies involving 190,000 children and teenagers from 44 countries were included in the systematic review. Seven studies involving 18,000 participants had sufficient data to be included in a meta-analysis on the association between overnutrition and iron deficiency. Overweight or obese children had a 51% increase in the odds of being iron deficient.
There was no difference in the risk of iron deficiency between obese (odds ratio 1.88, 95% confidence interval 1.33-2.43) and overweight children (1.31, 0.98-1.64).
There were insufficient data to explore the association between body weight and zinc or vitamin A status through meta-analyses. However, the available data did suggest there was an “exponential plateau curve relationship” between these factors, where children and teenagers who were underweight had the highest risk of being deficient, but there was no evidence for a higher risk in overweight or obese individuals.
Researchers suggested hepcidin – which regulates iron homeostasis – as a potential mechanism for the association between body weight and iron deficiency risk.
“Excess adiposity is associated with low grade inflammation… which [stimulates] the synthesis of acute phase proteins such as ferritin and hepcidin. Hepcidin prevents iron absorption from the enterocytes and iron release from splenic macrophages… [and] in the context of chronic disease with prolonged immune activation can lead to anaemia of chronic disease,” the researchers wrote.
“This would explain the difference between the observation of iron deficiency, but not zinc or vitamin A deficiencies, in children with overweight or obesity.”
