Satiety and Food Intake

This study investigates the effects of foods enriched with alternative protein sources, including edible insects, microalgae, hemp, and legumes, on appetite regulation, satiety, food preferences, and metabolic health in healthy adults and individuals with overweight. The study is part of the CIPROMED project, which aims to support sustainable and circular food systems in the Mediterranean area. The study consists of two phases. In the acute phase, participants will consume different protein-enriched bread products in a controlled setting following a randomized crossover design. Each participant will be exposed to multiple test conditions, allowing within-subject comparisons of postprandial responses. Outcomes assessed during this phase include satiety, hunger, food preference, craving, and short-term energy intake, measured using validated scales and dietary assessment tools. In the chronic phase, participants will follow structured dietary interventions over a longer period within a Mediterranean dietary framework. Participants will be assigned to different dietary patterns including alternative protein-based foods and control products. This phase aims to evaluate the effects of repeated consumption of alternative protein sources on metabolic parameters, gastrointestinal tolerance, nutritional status, and behavioral responses. The study aims to assess the acceptability and physiological effects of alternative protein sources and to compare their impact with that of traditional protein sources commonly used in Mediterranean diets.

Rationale: Healthy foods, including mixed nuts, may improve brain function, which is essential for cognitive and metabolic health, and may contribute to improved food intake regulation. It is therefore important to investigate the specific effects of walnuts on cerebral blood flow responses before and after intranasal insulin administration, as well as their associated functional benefits. The investigators hypothesize that long-term walnut consumption improves vascular function and insulin-sensitivity in the brain, thereby enhancing cognitive performance and appetite control in abdominally obese men and women. Objective: The primary objectives are to investigate in abdominally obese adults the effects of 24-week walnut consumption on (regional) vascular function and insulin-sensitivity in the brain, while the investigators will also assess changes in cognitive performance and appetite-related brain reward activity (secondary objectives). Cerebral blood flow responses before (brain vascular function) and after the administration of intranasal insulin spray (brain insulin-sensitivity) will be quantified by the non-invasive gold standard magnetic resonance imaging (MRI)-perfusion method Arterial Spin Labeling (ASL). Study design: This intervention study will have a randomized, controlled parallel design. The total study duration will be 24 weeks. Study population: Fifty-five abdominally obese men and (postmenopausal) women (aged 45-75 years) without a history of cardiovascular diseases or complaints will participate. This study population is expected to have a decreased cerebral blood flow at baseline and are also at increased risk of cognitive impairment, allowing for improvement by the intervention. Intervention: Study participants will receive daily 50 g (about 15% of energy) of raw walnuts (walnut intervention) or no walnuts (control intervention) for 24 weeks. Main study parameters/endpoints: At baseline and after 24 weeks (follow-up), participants will visit the research facilities for assessments. The primary endpoint is the difference in the cerebral blood flow response before and after intranasal insulin administration between the walnut and control intervention. Cognitive performance will be assessed, while the investigators will also focus on appetite-related brain reward activity (secondary outcomes).

The study investigates the sensory characteristics, consumer perception and the effect on satiety and food intake of the meal with added Chondrus crispus seaweed produced by Acadian Seaplants in Atlantic Canada.