Different Circulating Ghrelin Responses to Isoglucidic Snack Food in Healthy Individuals

The last decade has seen much debate on ghrelin as a potential target for treating obesity. Despite a close connection between snack food intake and obesity, snacking is controversially reviewed as a good habit in a healthy nutritional regimen. The aim of the study was to evaluate whether a different nutrient composition influences postprandial ghrelin levels and glucose increments induced by 6 isoglucidic snack food. 20 healthy individuals (10 M/10 F; BMI 23.1 +/- 0.5; age 33 +/- 0.67 years, mean and SE) from H San Raffaele Scientific Institute and Milan University were enrolled. The subjects underwent OGTT (50 g) and 6 isoglucidic test-meal loads to assess the ghrelin circulating levels and the area under glycemic curves induced by 6 commercial snacks. 3 h after hazelnut chocolate intake, ghrelin was significantly lower than with wafer chocolate intake (p < 0.002). As a response to all snacks, the glycemic curves were not different even though hazelnut chocolate showed the lowest glycemic curve. Moreover, snack fat content was found to be inversely correlated to 3-h plasma ghrelin levels (p < 0.0001; R-2 = 0.77) and positively associated with satiety scores (p < 0.02; R-2 = 0.28). Also energy load was inversely correlated to 3-h plasma ghrelin (p < 0.0001; R-2 = 0.73). Our results indicate that snack food administered in equivalent glucidic loads elicits postprandial ghrelin suppression and satiety ratings in different ways. Further studies are needed to elucidate the role of ghrelin as hunger-hormone in the regulation of energy balance.