Effect of Beverages Containing Different Doses of Alginate Fibers on Appetite, Energy Intake and Glycemia

Three different iso-caloric beverages will be tested in a double-blinded crossover design, in which 24 participants will be randomly assigned to the sequence of the test days separated by at least 5 days. Prior to the test days, the participants will follow a standardized fasting procedure: abstention from alcohol hard physical activity for 24 h; furthermore, consumption of the same evening meal no later than 8 pm on the night before all meal tests, after which time point they should be fasting. They are allowed 500 mL of water between 8 pm and the morning of the test days.

On each test day, the participants will meet at the department in a fasting state. After voiding they will be weighed, and a venflon catheter will be inserted in the antecubital vein, allowing repeated blood sampling throughout the test day. Baseline measurements of blood pressure, blood samples, and visual analogue scales (VAS) scores will be conducted at time point of -15 min. A second baseline blood sample will be drawn at time point 0, immediately after which the participants will consume the preload beverage (time point 0) with a 10 min time limit for consumption. After consumption of the preload beverage, blood samples will be taken and VAS scores completed at time points 15 and 30 min, and hereafter the he standardized breakfast will be served for which 15 minutes is allowed (time point 30 min). After the participants have finished the breakfast, blood samples will be drawn and VAS scores completed at time points 45, 60, 90, 120, 180, 210 and 240 min.

Hereafter, an ad libitum meal consisting of Pasta Bolognese will be served, and energy intake calculated, and the final VAS score will be completed at time point 270 min after the participants have finished their lunch. Before leaving, the participants will fill in a questionnaire related to gastrointestinal adverse events (AE).

As a pilot study, the first 6 participants to finish the study will be invited to participate in a fourth test day, on which capsules containing alginate fibers will be administered together with the placebo beverage. This fourth test day is not included in the randomization and will not be blinded for the participants.

Inclusion criteria

• Overweight (BMI 25-35 kg/m2)

Exclusion criteria

• Any food allergy, dislike or special diet of relevance to the study (e.g. vegetarian)
• Smoking
• Use of dietary supplements up to 1 month before the first meal test
• Pregnancy or lactation
• Daily use of prescription medication (except for oral contraceptives)
• Any known chronic illnesses
• Participation in other intervention studies
• Non-adherence to the protocol or lack of cooperation
• Blood donation within 3 months prior to the study