The Chocolate Almond Study - Relating Chewing to Satiation and Postprandial Response

The Impact of Almond Size in a White Chocolate Matrix on Satiation, Postprandial Glycemia & Lipemia, Chewing Exertion, Eating Rate, and Product Liking: A Randomized Crossover Trial

The goal of this clinical trial is to relate chewing behaviours to food intake and postprandial response for a texturally complex food matrix (almonds in white chocolate) in healthy young females. The main questions it aims to answer are:

• Does the presence or preparation of almonds (whole versus chopped) influence satiation, i.e., the amount consumed at an ad libitum meal?
• What is the correlation between chewing behaviour, satiation, and changes in postprandial glucose, triacylglycerols, and satiety ratings? Participants will attend the research centre fasted on three occasions to consume an ad libitum meal, complete questionnaires, and provide fasting and postprandial finger prick blood samples.

This study is investigating how the size and presence of almonds (whole vs. chopped) in a white chocolate matrix affect satiation (termination of eating) and postprandial satiety, glycemia, and lipemia. Over three visits, fasted healthy adult female participants will consume three types of white chocolate bark: one with whole almonds, one with chopped almonds, and one with just chocolate. The amount of each ad libitum meal consumed and eating time will be quantified to compare satiation between the confectionery products. Participants will rate their chewing experiences (e.g., exertion, liking, motivations to stop eating) and feelings of satiety up to 180 minutes using paper questionnaires. Participants will also provide finger prick blood samples for determination of glucose and triacylglycerol levels before and after eating each treatment, i.e., at baseline (0 minutes) and 120 (glucose) and 180 (triacylglycerols) minutes after eating. Overall, this study aims to provide insights into the role of food structure in influencing eating and metabolic response and ultimately how food choices can be optimized for better management of blood sugar, satiety, and lipemia to support cardiometabolic health. It is being complemented by a collaboration with researchers in the Department of Food Science at the University of Guelph (led by Prof. Lisa Duizer) examining sensory perception of these same texturally complex foods and the relationship between oral processing behaviour and bolus properties, as well as by in vitro digestion investigations of digestate properties and nutrient release to enable an integrated understanding linking food structure to eating behaviour and postprandial metabolism.

Inclusion Criteria:

• BMI between 18.5-27.9 kg/m^2 or waist circumference less than 88 cm
• No known food allergies or sensitivities
• Non-restrained eaters based on the Three Factor Eating Questionnaire
• No history of gastrointestinal diseases that may interfere with eating behaviour or digestion
• Not on medications that affect appetite, digestion, blood sugar regulation, saliva production, or chewing
• Stable medication use
• Non-smokers
• Not gained or lost significant weight during the past 3 months
• Regular monthly menstrual cycles
• Not pregnant, lactating, or post-menopausal

Exclusion Criteria:

• Diabetes or other metabolic disorders affecting glycemia and overall cardiometabolic health
• Any food allergies, intolerance, or sensitivities
• Any life-threatening allergy
• Pregnant or breastfeeding
• Participation in another clinical trial
• Alcohol consumption more than 14 drinks per week
• Smokers or those with a smoking history or more than 10 years
• Regular use of recreational drugs (e.g., marijuana, ecstasy, magic mushrooms)
• Restrained eater as defined by > 15 on the Three-Factor Eating Questionnaire
• Unusual sleep patterns
• Irregular breakfast consumption
• Recent weight changes or intended weight loss or gain or having lost or gained >10% of body weight within the last 6 months
• Using medications known to affect appetite, digestion, blood sugar regulation, lipids, or chewing (excluding oral contraceptives)
• Experiences dry mouth, in general or due to medication side effects
• Diagnosed with Sjogren's Syndrome (autoimmune condition linked to severe dry mouth)
• Inability to adhere to study protocols
• Not comfortable providing finger prick blood samples
• Avoids consuming almonds or chocolate
• Has temporomandibular joint disorder (TMJ)
• Has or history or oral cancer
• Recent dental or jaw surgery
• Avoids eating hard foods for concerns of dental fractures or for general oral health
• Individuals with dentures, braces, Invisalign, or other dental implants that cause difficulty chewing