Guarneiri, L.L., C.M. Paton, J.A. Cooper, 2022. Changes in body weight in response to pecan-enriched diets with and without substitution instructions: a randomised, controlled trial. J Nutr Sci. 11:e16. doi: 10.1017/jns.2022.14.
Substantial evidence suggests that regular tree nut consumption does not lead to changes in body weight (BW). However, these studies used a variety of dietary substitution instructions which may confound the interpretation of prior BW outcomes. The purpose of the present study was to examine the impact of daily pecan consumption, with or without isocaloric substitution instructions, on BW and composition. This was an 8-week randomised, controlled trial with three treatments: a nut-free control group (n 32) and two pecan groups. ADD (n 30) consumed pecans (68 g/d) as part of a free-living diet, and SUB (n 31) substituted the pecans (68 g/d) for isocaloric foods from their habitual diet. BW and total body fat percentage (BF) were measured, and theoretical changes in these outcomes if pecans were consumed without compensation were determined. BW increased in all groups across the intervention, and there was a trend (P = 0.09) for an increase in ADD (1.1 ± 0.2 kg) and SUB (0.9 ± 0.3 kg) compared to control (0.3 ± 0.2 kg). In addition, there was increased BF in SUB (1.0 ± 0.3 %; P = 0.005) but not ADD (0.1 ± 0.2 %) or control (-0.2 ± 0.3 %) There was a large difference in the actual v. theoretical change in BW regardless of pecan treatment (actual: 1.1 ± 0.2 and 0.9 ± 0.3 v. theoretical: 3.3 ± 0.0 and 3.2 ± 0.0 kg in ADD and SUB, respectively; P < 0⋅001). Furthermore, there was a difference in actual v. theoretical change in BF in ADD (0.1 ± 0.2 v. 1.2 ± 0.1 %; P = 0.002) but not SUB or control. In conclusion, daily pecan consumption for 8 weeks did not result in significant weight gain, regardless of dietary substitution instructions.
Guarneiri, L.L., C.M. Paton, J.A. Cooper, 2022. Appetite responses to pecan-enriched diets. Appetite. 173:106003. https://doi.org/10.1016/j.appet.2022.106003
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.
Carter, S., A.M. Hill, J.D. Buckley, S.‑Y. Tan, G.B. Rogers, A.M. Coates, 2022. Acute feeding with almonds compared to a carbohydrate‑based snack improves appetite‑regulating hormones with no effect on self‑reported appetite sensations: a randomised controlled trial. Eur. J. Nutr. 62:857–866.
Purpose: Early satiety has been identified as one of the mechanisms that may explain the beneficial effects of nuts for reducing obesity. This study compared postprandial changes in appetite-regulating hormones and self-reported appetite ratings after consuming almonds (AL, 15% of energy requirement) or an isocaloric carbohydrate-rich snack bar (SB). Methods This is a sub-analysis of baseline assessments of a larger parallel-arm randomised controlled trial in overweight and obese (Body Mass Index 27.5–34.9 kg/m2) adults (25–65 years). After an overnight fast, 140 participants consumed a randomly allocated snack (AL [n = 68] or SB [n = 72]). Appetite-regulating hormones and self-reported appetite sensations, measured using visual analogue scales, were assessed immediately before snack food consumption, and at 30, 60, 90 and 120 min following snack consumption. A sub-set of participants (AL, n = 49; SB, n = 48) then consumed a meal challenge buffet ad libitum to assess subsequent energy intake. An additional appetite rating assessment was administered post buffet at 150 min. Results: Postprandial C-peptide area under the curve (AUC) response was 47% smaller with AL compared to SB (p < 0.001). Glucose-dependent insulinotropic polypeptide, glucagon and pancreatic polypeptide AUC responses were larger with AL compared to SB (18%, p = 0.005; 39% p < 0.001; 45% p < 0.001 respectively). Cholecystokinin, ghrelin, glucagon-like peptide-1, leptin and polypeptide YY AUCs were not different between groups. Self-reported appetite ratings and energy intake following the buffet did not differ between groups. Conclusion: More favourable appetite-regulating hormone responses to AL did not translate into better self-reported appetite or reduced short-term energy consumption. Future studies should investigate implications for longer term appetite regulation.
Yaskolka, M.A., K. Tuohy K, M. von Bergen, R. Krajmalnik-Brown, U. Heinig, H. Zelicha, G. Tsaban, E. Rinott, A. Kaplan, A. Aharoni, L. Zeibich, D. Chang, B. Dirks, C. Diotallevi, P. Arapitsas, U. Vrhovsek, U. Ceglarek, S.-B. Haange, U. Rolle-Kampczyk, B. Engelmann, M. Lapidot, M. Colt, Q. Sun, I., 2021. The metabolomic-gut-clinical axis of Mankai plant-derived dietary polyphenols. Nutrients. 13(6):1866. https://doi.org/10.3390/nu13061866.
Background: Polyphenols are secondary metabolites produced by plants to defend themselves from environmental stressors. We explored the effect of Wolffia globosa ‘Mankai’, a novel cultivated strain of a polyphenol-rich aquatic plant, on the metabolomic-gut clinical axis in vitro, in-vivo and in a clinical trial. Methods: We used mass-spectrometry-based metabolomics methods from three laboratories to detect Mankai phenolic metabolites and examined predicted functional pathways in a Mankai artificial-gut bioreactor. Plasma and urine polyphenols were assessed among the 294 DIRECT-PLUS 18-month trial participants, comparing the effect of a polyphenol-rich green-Mediterranean diet (+1240 mg/polyphenols/day, provided by Mankai, green tea and walnuts) to a walnuts-enriched (+440 mg/polyphenols/day) Mediterranean diet and a healthy controlled diet. Results: Approximately 200 different phenolic compounds were specifically detected in the Mankai plant. The Mankai-supplemented bioreactor artificial gut displayed a significantly higher relative-abundance of 16S-rRNA bacterial gene sequences encoding for enzymes involved in phenolic compound degradation. In humans, several Mankai-related plasma and urine polyphenols were differentially elevated in the green Mediterranean group compared with the other groups (p < 0.05) after six and 18 months of intervention (e.g., urine hydroxy-phenyl-acetic-acid and urolithin-A; plasma Naringenin and 2,5-diOH-benzoic-acid). Specific polyphenols, such as urolithin-A and 4-ethylphenol, were directly involved with clinical weight-related changes. Conclusions: The Mankai new plant is rich in various unique potent polyphenols, potentially affecting the metabolomic-gut-clinical axis.
