Monosodium L-glutamate (MSG) on Satiety

The study is a randomized, 2-arm, double-blind, placebo-controlled, Latin square cross-over clinical trial to assess the impact of 0.5% MSG on total and meal/snack-specific energy intake and on subjective ratings of appetite compared to sodium. Subjects will partake in an adaptation visit to avoid first order effects and will not be included in the randomization.

A total of 75 healthy premenopausal women aged 19 to 60 y (inclusive) will be randomized to a sequence of test product administration. Participants will consume 1 of 2 test products, based on randomization sequence at each test period visit. Carrot and coriander soup (0.5% MSG + 0.48% salt) or negative control match for sodium (no MSG + 0.635% salt).

Participants will be required to meet several inclusion and exclusion criteria, which will be assessed at the screening visit, including a health questionnaire, medical/medication history, eating behavior questionnaires, depression questionnaire and anthropometric measurements. After assessment of the eligibility criteria (see Eligibility section) at the screening visit, qualified participants will be invited to participate in the study and will be familiarized with the completion of VAS for subjective ratings of hunger, fullness, satiety and desire to eat.

Over a 3-week period, participants will come to the test facility on three occasions to complete the study with a one week wash-out period between each visit. Participants will fast overnight before each visit and consume the same evening meal before each test day.

Participants arrive at the research center at approximately 8:15am. Right before serving the breakfast meal, participants will be asked to complete a satiety rating questionnaire (using visual analogue scale (VAS)). At 8:30am, participants will consume breakfast (cereal and milk). Immediately after eating breakfast participants will complete another VAS questionnaire as well as a taste/liking meal evaluation. Thereafter, VAS will be completed at 30 minute intervals.

Four hours after the breakfast meal (at 12:30pm), participants will be given one of the test products (carrot and coriander soup with or without MSG) based on their randomization schedule. Subjects will have 10 min to consume the soup in its entirety. Following test product/soup intake, subjects will complete a taste/liking meal evaluation and VAS questionnaire. Immediately after completion of the questionnaire (12:40pm), an ad lib lunch buffet will be provided and participants will be instructed to eat as much as or as little as they desire (within 30 min) until comfortably full, followed by completing a taste/liking meal evaluation and VAS questionnaire. Thereafter, VAS will be completed at 30 minute intervals.

At 3:30pm, participants will be provided with their second portion of the test product to consume within 10 min, followed by completing a taste/liking meal evaluation and VAS questionnaire. Immediately after test soup administration and completing questionnaires, an ad lib snack buffet will be provided and participants will be instructed to eat as much as or as little as they desire within 20 min, followed by completing a taste/liking meal evaluation and VAS questionnaire. VAS assessment will continue at 30 min intervals thereafter until 5:00pm ending the study day. Participants' next visit will be scheduled after 1 week wash-out period: all procedures are identical with the exception of the test treatment soup consumed by participants.

Inclusion criteria

• Healthy Premenopausal Female, 19 to 60 yrs old
• Non-smoker
• Non-heavy Drinker
• BMI between 25 and 39.9 inclusive at the screening visit (with average BMI 30)
• no reported current or previous metabolic diseases or chronic gastrointestinal disorders
• no medically prescribed diet, no slimming diet, used to eating 3 meals a day and snacking
• No blood donation during the study
• Reported intense sporting activities ≤ 10h/w
• Reported alcohol consumption ≤14 units/w
• Informed consent signed
• Recruitment form filled out

Exclusion criteria

• Smoker
• Vegetarian
• Disliking the meals provided on the test day, have allergy or intolerance to test products or study meals
• Use of medication which interferes with study measurements (as judged by the study physician).
• Possible eating disorder (measured by SCOFF questionnaire score >1)
• Current depression measured by BDI <10
• Pregnant during the study period or in the six months prior to pre-study investigation
• Reported lactating 6 weeks before pre-study investigation and during the study
• Reported weight loss or gain ≥ 10 % of bodyweight during a period of six months before pre-study examination.
• Eating disorder (measured by SCOFF questionnaire, ≥2 "yes" responses)
• Reported participation in another biomedical trial 1 month before the start of the study