Effect of exclusive breastfeeding and complementary feeding on infant growth and morbidity.

A cohort study was conducted in the Islamic Republic of Iran between January 1997 and February 1998 to compare the growth and morbidity of 100 infants who were exclusively breastfed for 6 months and 100 who received breast milk and complementary foods between 4-6 months. Infants' feeding pattern, weight and height were assessed and recorded. There were no significant differences in infants' weight and height gain between 4 and 6 months. The rate of diarrhoea between ages 4 and 6 months was significantly lower in exclusively breastfed infants than in complementary food-fed infants (11% versus 27%) and respiratory infections were also lower (23% versus 35%). We conclude that exclusive breastfeeding is superior at least until an infant is 6 months of age.