The effects of the fibre content and physical structure of carrots on satiety and subsequent intakes when eaten as part of a mixed meal

Previous research indicates that vegetables yield relatively high satiety scores, and that fibre content and structure may both contribute to these effects. This study evaluated the effects of the fibre content and physical structure (gross anatomy and cell structure) of carrots on postprandial satiety and subsequent food intakes when consumed as part of a mixed meal. Using a randomised, repeated-measures, within-subject cross-over design, young women consumed a standardised breakfast and test lunches on three occasions, 4 weeks apart. The test lunches (3329 kJ) comprised boiled rice (200 g) with sweet and sour sauce (200 g) that included chicken (200 g) and carrots (200 g) in three conditions: whole carrots (fibre and structure; n 34), blended carrots (fibre but no structure; n 34) or carrot nutrients (no fibre or structure; n 32). The carrot nutrients had the same energy, major nutrients and portion weight as the other two conditions. Post-lunch satiety was assessed by visual analogue scales. Intakes were covertly weighed at a meal eaten ad libitum (3 h later), and for the remainder of the day using food diaries. Compared with the meal with carrot nutrients, meals with whole carrots and blended carrots resulted in significantly (P < 0.05) higher satiety. There were significant (P < 0.05) differences between conditions in intakes at the meal eaten ad libitum and for the remainder of the day, and intakes consistently decreased in the order: carrot nutrients, blended carrots, whole carrots, indicating that both fibre content and structure played a role in these effects.