Efficacy of Nutrilite® All Plant Protein in Postprandial Glycemic Control: A Non-randomized, Controlled, Crossover Study

Glucose balance is essential for life and health. It's regulated by organs that absorb glucose after eating and by the liver that produces glucose during fasting. This study aimed to investigate the acute effect of Nutrilite® All Plant Protein (APP), administered as a preload in 250 mL spiced buttermilk, on glycemic response to a standardized 75 g oral glucose load in individuals with compromised blood glucose levels. The impact of APP, a plant-based dietary protein formulation, was assessed using a non-randomized, fixed-sequence, controlled crossover design to evaluate its potential as a nutritional intervention to improve glycemic response. Fourteen participants were enrolled in the study. Efficacy analyses were conducted in the complete paired efficacy population, defined as participants with usable paired glucose measurements at both intervention visits and all predefined time points (n = 10). Blood glucose spikes were better regulated with APP preload at almost all time points compared to the reference product (glucose). In this acute oral glucose tolerance test (OGTT)-based setting, participants maintained glucose values within the normoglycemic range for a longer duration after the APP preload condition than after the glucose-only reference condition. In the complete paired efficacy population (n = 10), the average incremental area under the curve (iAUC) for the reference product was 3049.5 ± 1290.45. In contrast, the average iAUC for APP combined with the reference product was 700.5 ± 688.74, representing a 78% reduction. This decrease in iAUC was statistically significant (p < 0.005). The significant reduction in iAUC suggests that APP may blunt acute glycemic excursions after a 75 g oral glucose challenge. These findings should not be directly extrapolated to mixed-meal settings without additional vehicle-controlled and meal-based studies. Furthermore, the findings should be interpreted as an acute reshaping of the OGTT glucose response curve rather than as evidence of uniformly improved glycemic control throughout the full 120-minute period.