Pabla Pardeep, Mallinson Joanne, Nixon Aline, Keeton Mia, Cooper Scott, Marshall Melanie, Jacques Matthew, Brown Sara, Johansen Odd Erik, Cuenoud Bernard, Karagounis Leonidas G, Tsintzas Kostas
MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom.
Nestlé Health Science, Vevey, Switzerland.
Am J Clin Nutr. 2025 Feb;121(2):232-245. doi: 10.1016/j.ajcnut.2024.12.022. Epub 2024 Dec 26.
Small nutritional preloads can reduce postprandial glucose excursions in individuals with and without metabolic syndrome or type 2 diabetes (T2D). However, most studies have focused on preloads administered before single meals and have predominantly used protein-based preloads.
To investigate the effects of sequential consumption of medium-chain triglycerides (MCT) and whey protein isolate (WPI) preloads before breakfast, lunch, and dinner on postprandial, diurnal, and 24-h glycaemia in individuals with T2D.
Participants with T2D were studied over 3 randomized 24-h periods. They consumed either water before standardized breakfast, lunch, and dinner (CONTROL), 15 g MCT before breakfast and water before lunch and dinner (MCT), or 15 g MCT before breakfast and 10 g WPI before lunch and dinner (MCT + WPI). Diurnal (08:00-23:00 h) and 24 h (08:00-08:00 h) glycaemia (incremental AUC [iAUC]) and glycaemic variability (%coefficient of variation [%CV]) were evaluated by continuous glucose monitoring. Postprandial glycaemia (PPG) after breakfast and lunch was assessed by arterialized blood glucose iAUC.
In 21 enrolled patients (8 males/13 females, mean ± standard deviation age 55.1 ± 8.5 y, body mass index 31.7 ± 4.3 kg·m, glycated hemoglobin 59 ± 12 mmol·mol) diurnal and 24-h iAUC were similar across interventions, whereas 24-h %CV was lower in MCT (16.8 ± 0.8%, P = 0.033) and MCT + WPI (16.1 ± 0.9%, P = 0.0004) than CONTROL (18.7 ± 0.9%). PPG iAUC was ∼17% lower after breakfast in MCT and MCT + WPI compared with CONTROL, but only the MCT + WPI lowered glucose by 20% (P = 0.002) over the entire day (08:30-17:30 h). Gastric inhibitory polypeptide (GIP) (P = 0.00004), peptide YY (PYY) (P = 0.01), and β-hydroxybutyrate (P = 0.0001) were higher in MCT and MCT + WPI than CONTROL. Subjective appetite ratings were lower after breakfast and lunch in MCT + WPI (P = 0.001).
Sequential consumption of MCT and WPI preloads did not affect diurnal or 24-h glycaemia but lowered PPG and 24-h glycaemic variability in individuals with T2D. These effects were associated with increased circulating β-hydroxybutyrate, PYY, and GIP, and suppression of appetite. This trial was registered at clinicaltrials.gov as NCT04905589 (https://clinicaltrials.gov/study/NCT04905589).
小型营养预负荷可降低患有和未患有代谢综合征或2型糖尿病（T2D）的个体的餐后血糖波动。然而，大多数研究集中于在单餐之前给予的预负荷，并且主要使用基于蛋白质的预负荷。
研究在早餐、午餐和晚餐前依次食用中链甘油三酯（MCT）和乳清蛋白分离物（WPI）预负荷对T2D个体的餐后、日间和24小时血糖的影响。
对患有T2D的参与者进行了3个随机的24小时研究期。他们在标准化早餐、午餐和晚餐前分别饮用了水（对照组）、早餐前饮用15克MCT且午餐和晚餐前饮用了水（MCT组），或早餐前饮用15克MCT且午餐和晚餐前饮用10克WPI（MCT+WPI组）。通过连续血糖监测评估日间（08:00-23:00时）和24小时（08:00-08:00时）血糖（增量AUC[iAUC]）和血糖变异性（变异系数百分比[%CV]）。通过动脉化血糖iAUC评估早餐和午餐后的餐后血糖（PPG）。
在21名入组患者（8名男性/13名女性，平均±标准差年龄55.1±8.5岁，体重指数31.7±4.3kg·m，糖化血红蛋白59±12mmol·mol）中，各干预组的日间和24小时iAUC相似，而MCT组（16.8±0.8%，P=0.033）和MCT+WPI组（16.1±0.9%，P=0.0004）的24小时%CV低于对照组（18.7±0.9%）。与对照组相比，MCT组和MCT+WPI组早餐后的PPG iAUC降低了约17%，但只有MCT+WPI组在一整天（08:30-17:30时）内使血糖降低了20%（P=0.002）。MCT组和MCT+WPI组的胃抑制多肽（GIP）（P=0.00004）、肽YY（PYY）（P=0.01）和β-羟基丁酸（P=0.0001）高于对照组。MCT+WPI组早餐和午餐后的主观食欲评分较低（P=0.001）。
依次食用MCT和WPI预负荷不会影响T2D个体的日间或24小时血糖，但可降低其PPG和24小时血糖变异性。这些作用与循环β-羟基丁酸、PYY和GIP增加以及食欲抑制有关。该试验在clinicaltrials.gov上注册为NCT04905589（https://clinicaltrials.gov/study/NCT04905589）。
