The committee recommends that clinical growth studies follow the study participants for the entire period when infant formula remains a substantial source of nutrients in the diets of the infants. In 1996, the FDA proposed a 120- day growth study. According to the committee, this may not be of suffi cient length. The rationale behind this conclusion is that exclusive human milk feeding is recommended for 4– 6 months. In the absence of human milk, the feeding of infant formula, intended as a human milk substitute, is recommended for the same period of time. Th us, the committee considers that, ideally, formula should be tested for the entire period for which it is intended to be fed as the sole source of infant nutrition (up to 6 months or ≈180 days, consistent with breastfeeding guidelines) rather than the currently proposed 120- day period. Furthermore, the committee considers that a 120- day growth study may not be of suffi cient length either to determine delayed effects or to understand longer- term effects of early
perturbations in growth.