Archive

Research Area: Body Weight/Satiety

The effect of high-polyphenol Mediterranean diet on visceral adiposity: the DIRECT PLUS randomized controlled trial.

Zelicha, H., N. Kloting, A. Kaplan, A. Yaskolka Meir, E. Rinott, G. Tsaban, Y. Chassidim,  M. Bluher, U. Ceglarek, B. Isermann, M. Stumvoll, R.N. Quayson, M. von Bergen, B. Engelmann, U.E. Rolle-Kampczyk, S.B. Haange, K.M. Tuohy, C. Diotallevi, I. Shelef, F.B. Hu, M.J. Stampfer, I. Shai, 2022. The effect of high-polyphenol Mediterranean diet on visceral adiposity: the DIRECT PLUS randomized controlled trial. BMC Medicine. 20(1):327. https://doi.org/10.1186/s12916-022-02525-8

Background: Mediterranean (MED) diet is a rich source of polyphenols, which benefit adiposity by several mechanisms. We explored the effect of the green-MED diet, twice fortified in dietary polyphenols and lower in red/processed meat, on visceral adipose tissue (VAT). Methods: In the 18-month Dietary Intervention Randomized Controlled Trial PoLyphenols UnproceSsed (DIRECT-PLUS) weight-loss trial, 294 participants were randomized to (A) healthy dietary guidelines (HDG), (B) MED, or (C) green-MED diets, all combined with physical activity. Both isocaloric MED groups consumed 28 g/day of walnuts (+ 440 mg/day polyphenols). The green-MED group further consumed green tea (3–4 cups/day) and Wolffia globosa (duckweed strain) plant green shake (100 g frozen cubes/day) (+ 800mg/day polyphenols) and reduced red meat intake. We used magnetic resonance imaging (MRI) to quantify the abdominal adipose tissues. Results: Participants (age = 51 years; 88% men; body mass index = 31.2 kg/m2; 29% VAT) had an 89.8% retention rate and 79.3% completed eligible MRIs. While both MED diets reached similar moderate weight (MED: − 2.7%, green-MED: − 3.9%) and waist circumference (MED: − 4.7%, green-MED: − 5.7%) loss, the green-MED dieters doubled the VAT loss (HDG: − 4.2%, MED: − 6.0%, green-MED: − 14.1%; p < 0.05, independent of age, sex, waist circumference, or weight loss). Higher dietary consumption of green tea, walnuts, and Wolffia globosa; lower red meat intake; higher total plasma polyphenols (mainly hippuric acid), and elevated urine urolithin A polyphenol were significantly related to greater VAT loss (p < 0.05, multivariate models). Conclusions: A green-MED diet, enriched with plant-based polyphenols and lower in red/processed meat, may be a potent intervention to promote visceral adiposity regression.

Effect of walnut predinner snack on mealtime hunger and nutrient intake among university students. 

Wilson, T., L.S. DeVaan, M.E. LaCasse, E.M. Gile, M.J. Weis, M.D. Ahmann, G.I. Schnellman, M.T. Lenz, T.L. Hooks, 2022. Effect of walnut predinner snack on mealtime hunger and nutrient intake among university students. J Medicinal Food. 25(1):89–96. https://doi.org/10.1089/jmf.2021.0092

Freshman-15 is a phenomenon of first-year university students resulting in weight gain partly due to new cafeteria eating patterns and stress. This study determined if a premeal walnut snack alters planned eating behavior and mealtime nutrient intake during a subsequent buffet-model meal. Healthy university students (n = 36; 18.1 ± 0.5 years; body mass index: 23.6 ± 3.9) received three treatments (90 min premeal) in randomized order on 3 consecutive days: (1) snack of 190 Cal (1 oz) of walnuts (WS), (2) snack of 190 Cal of gummy candy (GS), or (3) no snack (NS; control) before a standard cafeteria dinner (1760 Cal). Visual analog scale (VAS) surveys were administered before and after dinner, and caloric intake was determined. Premeal VAS desire to eat was lower after WS and GS than NS, whereas the sense of hunger and sense of fullness were higher after WS and GS compared with NS. Postmeal VAS was not different between treatments. Mealtime calories, total fat, saturated fat, cholesterol, protein, sodium, fiber, and sugar consumed after WS were significantly less than NS. Total fat and sodium consumed after GS did not significantly differ from NS. Mealtime total fat, sodium, and fiber for WS were significantly less than GC, and a trend was observed for total calories. Differences in calorie intake were not observed between treatments when snack calories were included as part of the mealtime caloric intake. These findings could be helpful for promoting WS and to a lesser degree GS for increased satiety before meals possibly leading to reduced food intake during dinner by university students.

Diet-induced fasting ghrelin elevation reflects the recovery of insulin sensitivity and visceral adiposity regression.

Tsaban, G., A. Yaskolka Meir, H. Zelicha, E. Rinott, A. Kaplan, A. Shalev, A. Katz, D. Brikner, M. Blüher, U. Ceglarek, M. Stumvoll, M.J. Stampfer, I. Shai, 2022. Diet-induced fasting ghrelin elevation reflects the recovery of insulin sensitivity and visceral adiposity regression. JCEM. 107(2):336–345. https://doi.org/10.1210/clinem/dgab681

Aims: Lower fasting-ghrelin-levels (FGL) are associated with obesity and metabolic syndrome. We aimed to explore the dynamics of FGL during weight-loss and its metabolic and adiposity-related manifestations beyond weight-loss. Methods: A secondary analysis of a clinical trial where we randomized participants with abdominal-obesity/dyslipidemia to one of three diets: healthy-dietary-guidelines (HDG), Mediterranean diet (MED), or green-MED diet, all combined with physical activity (PA). Both MED diets were similarly hypocaloric and included 28g/day walnuts. The green-MED group further consumed green tea (3-4 cups/day) and a Wolffia-globosa (Mankai) plant green-shake. We measured FGL and quantified body fat depots by Magnetic-Resonance-Imaging at baseline and after 18-months. Results: Among 294 participants [body-mass-index=31.3kg/m 2;FGL=504±208pg/mL; retention rate=89.8%], lower FGL were associated with unfavorable cardiometabolic parameters as higher visceral-adipose-tissue (VAT), intra-hepatic fat, leptin, and blood pressure (p<0.05 for all; multivariate models). ΔFGL18-month differed between men (+7.3+26.6%) and women (-9.2+21.3%,p=0.001). After 18-months of moderate and similar weight loss among the MED-groups, FGL increased by 1.3%, 5.4%, and 10.5% in HDG, MED, and green-MED groups, respectively (p=0.03 for green-MED vs. HDG), sex-stratified analysis revealed similar changes in men only. Among men, FGL18-month elevation was associated with favorable changes in insulin resistance profile and VAT regression, after adjusting for relative weight-loss (HbA1c:r=-0.216; homeostatic-model-of insulin-resistance:r=-0.154; HDL-c:r=0.147;VAT:r=-0.221;p<0.05 for all). , Insulin resistance and VAT remained inversely related with FGL elevation, beyond which was explained by weight-loss (residual regression analyses;p<0.05). Conclusions: Diet-induced FGL elevation may reflect insulin sensitivity recovery and VAT regression beyond weight-loss, specifically among men. Green-MED diet is associated with greater FGL elevation.

Appetite responses to pecan-enriched diets.

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.