Infants born to young mothers who are not fully developed are found to have low birth weights.[13] The level of maternal nutrition during pregnancy can affect newborn body size and composition.[6] Iodine-deficiency in mothers usually causes brain damage in their offspring, and some cases cause extreme physical and mental retardation. This affects the children’s ability to achieve their full potential. In 2011 UNICEF reported that thirty percent of households in the developing world were not consuming iodized salt, which accounted for 41 million infants and newborns in whom iodine deficiency could still be prevented.[14] Maternal body size is strongly associated with the size of newborn children.[6]