Effect of 100% Orange Juice on Food Intake and Glycemic Response in Adults

The purpose of this study is to determine the effects of 100% orange juice on short-term food intake (FI), satiety, post-prandial glycemia and mood in healthy adults. We hypothesize that the consumption of 100% orange juice in the pre-meal environment will improve satiety signals and mood, and suppress FI through its effect on post-prandial glycemia.

A randomized within-subjects repeated measures design will be employed. Study visits will take place in the morning, separated one-week apart. At each session, participants will consume one of three treatments: 1) 100% orange juice; 2) orange flavoured drink; or 3) water. Glycemic response will be measured for 60 minutes (baseline (0 minutes), 15 minutes, 30 minutes, 45 minutes and 60 minutes) post-treatment via finger prick. Blood glucose measures will also be provided over 24 hours via a Dexcom G6 continuous glucose monitoring (CGM) device. Subjective appetite, emotions and mood will be measured for 90 minutes min (baseline (0 minutes), 15 minutes, 30 minutes, 45 minutes, 60 minutes and 90 minutes) post-treatment. At 60 minutes, participants will consume an ad libitum pizza lunch to evaluate food intake. After lunch, participants will be sent home with a rest-of-the-day food intake sheet to record their snacks, meals, and beverages, as well as a physical activity log to record their physical activity for the rest of the day following test session completion.