Serum ghrelin concentration, fasting time and feeding in infants.

Background: Data on hormonal feeding control in infants in the first months of life according to the kind of feeding are scanty. Aim: To evaluate whether serum ghrelin could be involved in feeding behaviour control of breast-fed (BF) and formula fed (FF) infants. Methods: We studied 50 AGA healthy term infants aged 1-6 months of age. Serum ghrelin concentration was determined by RIA. Fasting time (measured as the difference between the time of the last meal and the time of blood collection) and number of meals were recorded. Results: A positive correlation between serum ghrelin levels and fasting time emerged in FF infants (r = 0.752; p <0.001) but not in BF infants (r = 0.345; p = 0.072). Conclusions: Circulating ghrelin concentration correlates positively with fasting time in FF infants; these infants have higher serum ghrelin concentration, longer fasting time and fewer meals than BF infants. These observations suggest a possible influence of early feeding on mechanisms regulating satiety and feeding behaviour.