Undernourished infants are at a higher risk of lung restriction, suggests a recent study. The research by a team of scientists at the University of Arizona Health Sciences, published in the Lancet Respiratory Medicine, revealed three risk factors –- maternal nutritional problems during pregnancy, low birth weight for gestational age and below normal weight in childhood — that were significantly linked to adult spirometric restriction. The researchers wrote that the participants who were underweight in childhood had a risk of developing lung restriction that was three times higher than children with normal weight.