The objective of this study was to investigate the impact of the Mediterranean diet (MedDiet) consumed before and after weight loss on eating behavioral traits as measured by the Three-Factor Eating Questionnaire (TFEQ) in men with metabolic syndrome (MetS). In this fixed sequence study, 19 men with MetS (National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATPIII) criteria), aged between 24 and 62 years, first consumed a five-week standardized North American control diet followed by a five-week MedDiet, both under weight-maintaining controlled-feeding conditions. This was followed by a 20-week caloric restriction weight loss period in free-living conditions, without specific recommendations towards adhering to the principles of the MedDiet. Participants were finally subjected to a final five-week MedDiet phase under isoenergetic controlled-feeding conditions. The MedDiet before weight loss had no impact on eating behavioral traits. Body weight reduction by caloric restriction (-10.2% of initial weight) was associated with increased cognitive restraint (p < 0.0001) and with reduced disinhibition (p = 0.02) and susceptibility to hunger (p = 0.01). Feeding the MedDiet for five weeks under isoenergetic conditions after the weight loss phase had no further impact on eating behavioral traits. Results of this controlled-feeding study suggest that consumption of the MedDiet per se has no effect on eating behavioral traits as measured by TFEQ, unless it is combined with significant weight loss.
Keywords: Mediterranean diet; Three-Factor Eating Questionnaire; cognitive restraint; disinhibition; metabolic syndrome; susceptibility to hunger; weight loss.