Little is known about postprandial release of serum ghrelin, glucagon and glucagon-like peptide-1 (GLP-1) in relation with differing fasting insulin levels. We hypothesized that these hormones are affected by insulin resistance and hence we compared different postprandial responses of GLP-1, glucagon and ghrelin in subjects with relatively high (RHI) or relatively low (RLI) fasting insulin levels. The trial was a randomized cross-over study with four different meal conditions. Fourteen non-obese or obese, healthy, men and 14 women were randomly assigned to the order of supervised intake of a 750 kcal drink with the same protein contents but with 20 energy-percent (E%) or 55 E% from carbohydrates, and the remaining energy from fat. Participants were also randomized to consume the drinks as one large beverage or as five 150 kcal portions every 30 minutes. The 28 subjects were divided in two equally sized groups based on fasting insulin levels. Statistics was done with general linear mixed model. Fasting insulin levels were three-fold higher in the group with RHI compared with the RLI group (RHI: 1004±510 pg/ml, RLI: 324±123 pg/ml, p<0.0005). Serum GLP-1 was highest in the RHI group after both single meals and after 5 drinks and following highand low carbohydrate meals (both p≤ 0.002) and this was the case also for glucagon levels (both p≤0.018), while ghrelin levels did not differ between groups. Thus, subjects with RHI displayed both higher postprandial serum GLP-1 and glucagon than the participants with RLI, suggesting that glucagon could play a role in the advent of dysglycemia by insulin resistance.