The Mediterranean diet increases glucagon‐like peptide 1 and oxyntomodulin compared with a vegetarian diet in patients with type 2 diabetes: A randomized controlled cross‐over trial

Aim To compare a Mediterranean diet (MED) with a high‐fibre vegetarian diet (HFV) in terms of hunger‐satiety perception through post‐prandial assessment of appetite‐related hormones glucagon‐like peptide 1 (GLP‐1) and oxyntomodulin, as well as self‐rated visual analogue scale (VAS) quantification, in overweight/obese subjects with type 2 diabetes (T2D). Materials and methods Twelve T2D subjects (Male to female ratio = 7:5), mean age 63 ± 8.5 years, were enrolled in a randomized, controlled, crossover study. Participants consumed an MED meal as well as an isocaloric meal rich in complex carbohydrate as well as an isocaloric MED meal in two different visits with a 1‐week washout period between the two visits. Appetite ratings, glucose/insulin, and gastrointestinal hormone concentrations were measured at fasting and every 30’ until 210’ following meal consumption. Results GLP‐1 and oxyntomodulin levels were significantly higher following MED meal compared with HFV meals (210’ area under the curve, p < 0.022 and p < 0.023, respectively). Both MED and HFV meal resulted in a biphasic pattern of GLP‐1 and oxyntomodulin, although MED meal was related to a delayed, significantly higher second GLP‐1 peak at 150’ compared with that of HFV meal (p < 0.05). MED meal was related to lower glucose profile compared with HFV meal (p < 0.039), whereas we did not observe significant changes in terms of self‐reported VAS scores and insulin trend. Conclusions In T2D overweight/obese subjects, an MED meal is more effective than a HFV meal in terms of post‐prandial plasma glucose homoeostasis and GLP‐1 and oxyntomodulin release. These changes were not confirmed by VAS appetite self‐assessment over a 210’ period.