Ghrelin secretion is modulated in a nutrient- and gender-specific manner

Summary background Ghrelin is a potent GH secretagogue that also plays an important role in appetite and weight regulation. Ghrelin increases hunger and food intake, and its levels decrease after a standard meal or glucose. objective To examine the effects of standard oral glucose, lipid and protein loads on ghrelin levels, investigating the possibility that these responses may be modulated by several anthropometric and metabolic factors. subjects and methods There were 24 adult nondiabetic subjects (13 men/11 women; mean age 55·3 ± 2·9 years, range 26–74 years). Each participant underwent one or more of the following nutrient loads: (i) a standard oral glucose (75 g) load (n = 18); (ii) an oral lipid load (40 g, with 24 g saturated fat; n = 13); (iii) an oral protein load (40 g; n = 11). results Fasting ghrelin levels were negatively related to body mass index (BMI; r =−0·47; P = 0·02), waist circumference (r = −0·58; P = 0·0028), waist/hip ratio (r = −0·56; P = 0·0046), fasting insulin (r = −0·44, P = 0·03), and homeostasis model assessment insulin resistance index (HOMA‐R; r = −0·43, P = 0·034). Glucose load induced a decrease in ghrelin levels (P