The umami seasoning, monosodium L-glutamate (MSG), has been shown to increase satiety in normal body weight adults, although the results have not been consistent. The satiety effect of MSG in overweight and obese adults has not been examined yet. The objective of the present study was to investigate the effect of MSG in a vegetable soup on subsequent energy intakes as well as food selection in overweight and obese adult women without eating disorders. A total of sixty-eight overweight and obese women (BMI range: 25·0-39·9 kg/m²), otherwise healthy, were recruited to our study. A fixed portion (200 ml) of control vegetable soup or the same soup with added MSG (0·5 g/100 ml) was provided 10 min before an ad libitum lunch and an ad libitum snack in the mid-afternoon. The control soup had equivalent amount of Na to the soup with added MSG. Energy intakes at the ad libitum lunch and ad libitum snack time after the soup preload were assessed using a randomised, double-blind, two-way cross-over design. The soup with MSG in comparison with the control soup resulted in significantly lower consumption of energy at lunch. The addition of MSG in the soup also reduced energy intake from high-fat savoury foods. The soup with MSG showed lower but no significant difference in energy intake at mid-afternoon. The addition of umami seasoning MSG in a vegetable soup may decrease subsequent energy intake in overweight and obese women who do not have eating disorders.
Keywords: Energy intake; Food choice; MSG monosodium l-glutamate; Monosodium l-glutamate; Overweight and obese women; Satiety; Umami; VAS visual analogue scale.