The goal of this clinical trial is to how supplementation with beta -glucan during two days of caloric and carbohydrate restriction impacts subjective appetite and gastrointestinal appetite hormones in healthy overweight adults. In addition, the study aims to investigate the impact on gastric emptying since appetite and energy intake following food or supplement consumption can also relate to their impact on gastric emptying and as reduced hunger and enhanced satiety have been reported to be linked with delayed gastric emptying. The study will also investigate how these interactions impact after meal responses of insulin and glucose and thus insulin sensitivity. The caloric restriction during breakfasts and dinners will be achieved by low-calorie ready meals in the format of the counterweight PRO800 diet and lunches will be low in carbohydrates. It aims to test whether the addition of β-glucan to calorie and carbohydrate-restricted meals amends postprandial responses of appetite hormones and subjective appetite.

participated will be assigned in double-blinded randomised crossover study, intervention group will be supplemented with 3g beta-glucan and the control group supplemented with 3g placebo.

This will be a randomised crossover study which will be conducted on overweight and obese women with BMI of 27-35 kg/m2 and 18 -50 years old. Subjects will conduct two experimental trials, each lasting over 2 days and involving the consumption of two low-calorie meal replacements, one for breakfast and another one for dinner, and a low carbohydrate lunch meal for 2 consecutive days. In one trial, during each meal participants will take 3g of beta-glucan supplement and 3 g of cellulose as a placebo will be taken in another trial. On day 1 of each trial, a low-calorie breakfast will be consumed at the metabolic investigation laboratory at New Lister Building (NLB) of Glasgow Royal Infirmary and low carbohydrate lunch and low-calorie dinner at home. On day 2, breakfast and lunch will be consumed at the laboratory. On day 2, prior to the breakfast, 1000mg of paracetamol will be taken, and blood samples, breath hydrogen tests, appetite questionnaires and metabolic rate measurements will be obtained for 7 hours after the completion of breakfast. Trials will be separated by a 7-day washout period. All measurements will be collected at New Lister Building (NLB). Prior to the main experimental trials, participants will be asked to undergo a screening session which includes answering a health screening questionnaire and undergoing measurements of height, body weight, body composition and resting energy expenditure.

Inclusion Criteria:

Participants will be asked to confirm whether they had stable body weight for at least 3 months and are not following a diet to gain or lose weight. They will also be asked to confirm that they are non-smokers, not on long-term medication, not pregnant or lactating, and have no known food allergies to the ingredients in test meals and to Paracetamol.

Exclusion Criteria:

Participants will be excluded if they are smokers and have irregular menstruation cycles, use any type of medication, exercised more than 75min a week, were pregnant or lactating. Participants will be required to be free of any medical condition, including having food allergies and stable body weight for at least 3 months preceding the study. Participants will be excluded if they are allergic to paracetamol and any types of food and were following any weight loss diet for the last 3 months, are vegan or vegetarian or follow any diet other than the typical Western diet. Participants will be expected to be not on any kind of dietary supplement at the time of the study.