Appetite responses to pecan-enriched diets

Abstract

Research suggests that tree nuts improve satiety during an acute meal, but the effects of daily consumption are less clear. The purpose of this study was to examine the impact of daily pecan consumption on markers of appetite in adults at-risk for cardiovascular disease (CVD). This was an 8-week, randomized, controlled trial with three treatments: two pecan groups and a nut-free control group (n = 16). The ADD group (n = 15) consumed pecans (68 g) as part of a free-living diet, and the SUB group (n = 16) substituted the pecans (68 g) for isocaloric foods from their diet. At pre- and post-intervention, a high-fat meal was consumed with 3.5 h postprandial blood draws and visual appetite scales (VAS) to determine changes in cholecystokinin (CCK), peptide YY (PYY), ghrelin, and subjective appetite. Participants also completed VAS questionnaires once/h for the next 5 h and recorded dietary intake. Although no differences between groups (p > 0.05), there was an increase in postprandial CCK and PYY and suppression of postprandial ghrelin within ADD (p ≤ 0.05) from pre-to post-intervention. Across the entire day, the decreases in prospective consumption and desire to eat were greater in ADD vs SUB (-79 ± 41 vs 11 ± 26 mm/9 h; p = 0.05) and ADD vs control (-64 ± 39 vs 23 ± 29 mm/9 h; p = 0.05), respectively. There was also a non-significant tendency for a greater decrease in overall appetite in ADD vs control (-67 ± 46 vs 20 ± 27 mm/9 h; p = 0.06). Within ADD, overall appetite, prospective consumption, and desire to eat decreased, and fullness increased from pre-to post-intervention (p ≤ 0.05 for all). There were no changes in self-reported energy intake on test days or other changes within or between groups. In conclusion, adding pecans to the daily diet improves subjective and physiological markers of postprandial appetite in adults that are at-risk for CVD.

Keywords: Cholecystokinin; Ghrelin; Hunger; Peptide YY; Satiety; Tree nuts; Visual analog scale.