The Effect of Green-Mediterranean Diet on Abdominal Fat Tissues, Adipokines, and Metabolome Profiles: Randomized Controlled Intervention Trial.
: Awarded HANEGEV Ph.D. scholarship Travel award to the highest scoring abstract, 41st ESPEN Congress. Poland. Recognition of Excellence in Bio-Medical Research award. Dean award of Ph.D. excellence. Awarded Kreitman post-doctoral scholarship

Student thesis: Doctoral Thesis


Objective: To compare the postprandial and overnight glycemic response using a novel green aquatic plant thought to provide a dietary source for high-quality protein with an iso-carbohydrate/protein/caloric dairy shake.

Research design and methods: This is a randomized controlled crossover trial among 20 abdominally obese participants (age 51.4 years; fasting plasma glucose 110.9 mg/dL), who were allocated to replace dinner with either, first, a green shake containing Wolffia globosa duckweed (Mankai: specific-strain) or an iso-carbohydrate/protein/calorie yogurt shake. A 2-week flash glucose-monitoring system was used to assess postmeal glucose dynamics (6 net administration days; 97 observation days in total). We further obtained from each participant dietary/daily activity/satiety scale/sleep logs. Participants were recruited from the green-Mediterranean diet arm of the 18-month Dietary Intervention Randomized Controlled Trial-Polyphenols Unprocessed (DIRECT-PLUS) study.

Results: Wolffia globosa Mankai elicited a lower postprandial glucose peak compared with yogurt (∆peak = 13.4 ± 9.2 vs. 19.3 ± 15.1 mg/dL; P = 0.044), which occurred later (77.5 ± 29.2 vs. 59.2 ± 28.4 min; P = 0.037) and returned faster to baseline glucose levels (135.8 ± 53.1 vs. 197.5 ± 70.2 min; P = 0.012). The mean post-net incremental area under the curve (netAUC) was lower with Wolffia globosa up to 60 and 180 min (netAUC 60 min: 185.1 ± 340.1 vs. 441.4 ± 336.5 mg/dL/min, P = 0.005; netAUC 180 min: 707.9 ± 1,428.5 vs. 1,576.6 ± 1,810.1 mg/dL/min, P = 0.037). A Wolffia globosa-based shake replacing dinner resulted in lower next-morning fasting glucose levels (83.2 ± 0.8 vs. 86.6 ± 13 mg/dL; P = 0.041). Overall, postprandial glucose levels from the shake administration until the next morning were lower in the Wolffia globosa Mankai green shake compared with the yogurt shake (P < 0.001). Overnight sleep duration was similar (378.2 ± 22.4 vs. 375.9 ± 28.4 min; P = 0.72), and satiety rank was slightly higher for the Wolffia globosa shake compared with the yogurt shake (7.5 vs. 6.5; P = 0.035).

Conclusions: Wolffia globosa Mankai duckweed may serve as an emerging alternative plant protein source with potential beneficial postprandial glycemic effects.
Awarded HANEGEV Ph.D. scholarship. Awarded Kreitman postdoctoral scholarship
Date of Award2022
Original languageEnglish
Awarding Institution
  • Ben-Gurion University of the Negev
SupervisorIris Shai (Supervisor) & Ilan Shelef (Supervisor)

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