Early food supplementation reduced the level of stunting from early infancy up to 54 months of age among boys ( average difference - 6.5 % units , 95 % confidence interval [ CI ] 1.7-11 .3 , p = 0.01 ) but not among girls ( average difference - 2.4 % units , 95 % CI -2.2 -7.0 , p = 0.31 ) .