Background: Consuming large doses of whey protein (WP) ∼30 minutes before high-glycemic load meals reduces postprandial glycemia (PPG). However, it is unclear if this effect is retained at smaller doses of WP, ingested at realistic times before typical meals. Moreover, as central obesity is associated with elevated PPG, WP may offer benefit in improving PPG within such individuals. We examined the PPG responses to breakfast following consumption of a small WP shot in centrally obese and lean males.

Methods: In a randomized-crossover design, 7 lean (BMI 24.3±1.5; waist circumference 79.3±7.1 cm; waist/hip ratio [WHR] 0.83±0.04) and 9 centrally obese (34.6±1.9; 112.8±10.2 cm; 0.97±0.1) age-matched, adult males performed two 240 minutes mixed-meal tests, 7d apart. After an overnight fast, participants consumed either a 100ml ready-to-drink WP shot (15g Protein) or 100ml water (CON) 10 minutes before a typical breakfast meal. Interval blood samples were collected for the measurement of plasma glucose. Data (mean±SD) were analyzed by a mixed-design ANOVA and Pearson’s correlation with significance accepted as p≤0.05.

Results: WP reduced early PPG AUC0-60min by 22±9.3% and 13.1±10% in lean and obese males, respectively, vs. CON (p<0.01). Obese males had greater AUC0-60min following WP vs. lean (p=0.02) with no differences after CON (p=0.62). Total trial glucose AUC0-240min was comparable between conditions in both groups (p>0.05). WP reduced peak PPG vs. CON (lean: -26.5±7% [p<0.001]; obese: -16.4±9.8% [p<0.01]) with a tendency for more marked reductions within lean males (p=0.052). Central obesity (WHR) was associated with greater increases in glucose from fasting values, despite WP consumption (r=0.7; p<0.01).

Conclusion: Consuming a palatable, ready-to-drink WP shot before breakfast attenuates early elevations in PPG and reduces hyperglycemia in lean and centrally obese males. Central obesity predicts the glucose lowering effect of WP and may limit its application in this group.

Disclosure

K. Smith: None. G.S. Taylor: None. N. Okwose: None. D.M. Allerton: None. L.H. Brunsgaard: Employee; Self; Arla Foods Ingredients. E.J. Stevenson: None. D.J. West: Research Support; Self; Arla Foods Ingredients, Dexcom, Inc.

Funding

Arla Foods Ingredients Group P/S

© 2019 by the American Diabetes Association.
2019
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