Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom.
Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom.
J Nutr. 2023 Oct;153(10):2842-2853. doi: 10.1016/j.tjnut.2023.08.008. Epub 2023 Aug 7.
Typical breakfast foods are rich in carbohydrate, so they not only elevate blood glucose during the morning, but also elicit a second-meal effect that can attenuate blood glucose responses in the afternoon.
To determine whether a reduced-carbohydrate protein-enriched breakfast can elicit similar effects on glucose control later in the day but without hyperglycemia in the morning.
In a randomized crossover design, 12 healthy men and women (age 22 ± 2 y, BMI 24.1 ± 3.6 kg·m; Mean ± SD) completed 3 experimental conditions. In all conditions, participants consumed an ad libitum lunch at 1200 ± 1 h but differed in terms of whether they had fasted all morning (control) or had consumed a standardized porridge breakfast at 0900 ± 1 h (320 ± 50 kcal; prescribed relative to resting metabolic rate) that was either carbohydrate-rich (50 ± 10 g CHO) or protein-enriched (that is, isoenergetic substitution of carbohydrate for 15 g whey protein isolate).
The protein-enriched breakfast reduced the morning glycemic response (iAUC 87 ± 36 mmol·L·180 min) relative to the carbohydrate-rich breakfast (119 ± 37 mmol·L·180 min; P = 0.03). Despite similar energy intake at lunch in all 3 conditions (protein-enriched 769 ± 278 kcal; carbohydrate-rich 753 ± 223 kcal; fasting 790 ± 227 kcal), postlunch insulinemic responses were markedly attenuated when breakfasts had been consumed that were either protein-enriched (18.0 ± 8.0 nmol·L·120 min; P = 0.05) or carbohydrate-rich (16.0 ± 7.7 nmol·L·120 min; P = 0.005), relative to when lunch was consumed in an overnight fasted state (26.9 ± 13.5 nmol·L·120 min).
Breakfast consumption attenuates insulinemic responses to a subsequent meal, achieved with consumption of energy-matched breakfasts typically high in carbohydrates or enriched with whey protein isolate relative to extended morning fasting.
NCT03866720 (clinicaltrials.gov).
典型的早餐食品富含碳水化合物，因此它们不仅会使早上的血糖升高，而且还会产生第二餐效应，从而减弱下午的血糖反应。
确定低碳水化合物、富含蛋白质的早餐是否会对一天中稍后的血糖控制产生类似的影响，但不会导致早上的血糖升高。
采用随机交叉设计，12 名健康男性和女性（年龄 22 ± 2 岁，BMI 24.1 ± 3.6 kg·m；平均值 ± 标准差）完成了 3 种实验条件。在所有条件下，参与者均在 12：00 ± 1 时随意进食午餐，但早餐有所不同，要么是禁食整个上午（对照组），要么是在 09：00 ± 1 时摄入一种标准化的粥早餐（320 ± 50 千卡；根据静息代谢率规定，相对热量），早餐中碳水化合物含量丰富（50 ± 10 g CHO）或富含蛋白质（即用 15 g 乳清蛋白分离物替代碳水化合物的等能替代）。
富含蛋白质的早餐使早晨的血糖反应（iAUC 87 ± 36 mmol·L·180 min）相对于富含碳水化合物的早餐（119 ± 37 mmol·L·180 min；P = 0.03）降低。尽管在所有 3 种条件下午餐的能量摄入相似（富含蛋白质的早餐为 769 ± 278 kcal；富含碳水化合物的早餐为 753 ± 223 kcal；禁食的早餐为 790 ± 227 kcal），但当早餐分别为富含蛋白质（18.0 ± 8.0 nmol·L·120 min；P = 0.05）或富含碳水化合物（16.0 ± 7.7 nmol·L·120 min；P = 0.005）时，午餐后胰岛素反应明显减弱，而在禁食过夜的状态下（26.9 ± 13.5 nmol·L·120 min）。
早餐的摄入会减弱对后续餐的胰岛素反应，通过摄入通常富含碳水化合物的能量匹配早餐或富含乳清蛋白分离物的早餐来实现，而不是延长早晨禁食时间。
NCT03866720（clinicaltrials.gov）。
