The possible long-term effects of prolonged breastfeeding in preventing obesity have led to the reconsideration of different growth curves of breastfed and formula-fed infants in the light of haematochemical markers. Leptin, ghrelin, insulin-like growth factors and other compounds may not only represent mediators involved in the metabolism of fat tissues, but may also potentially be able to explain the complex relationships between the gastrointestinal tract and the hypothalamic regulation of the sense of hunger and satiety.
Conclusion: Diet-related differences in the circulating levels of mediators implicated in energy metabolism during infancy might explain anthropometric and behavioural differences between breastfed and formula-fed infants with potential long-term consequences.