When children surveyed were 4 months and 1 year of age, mothers were questioned in detail concerning breastfeeding practices, use of milk formulas, and other aspects of infant diet. (pediatrics.aappublications.org)
We evaluated infant diet from birth until the time of stool collection by telephone questionnaires that included questions regarding the duration of breastfeeding and the timing of formula introduction, if any. (jamanetwork.com)
There has been extensive research into the developmental consequences of various components of infant diet. (academic.oup.com)