Gipson Elizabeth Z, Deru Landon S, Graves Parker G, Jacobsen Cameron G, Peterson Neil E, Bailey Bruce W
Department of Exercise Science, Brigham Young University, Provo, UT, 84602, USA.
Division of Physical Activity and Weight Management, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
Nutr Metab (Lond). 2025 Apr 15;22(1):32. doi: 10.1186/s12986-025-00920-5.
This study measured the impact of macronutrient composition of a pre-fast meal on time-to-ketosis and other metabolic indicators of glycemic control during a 24-hr fast within a population of older, sedentary, overweight adults.
Twenty-four adults who were over the age of 50, sedentary (< 150 min of weekly exercise), and overweight (BMI ≥ 27) participated in a randomized crossover study. Each of these inclusion criteria have been shown to increase the risk for the development of chronic diseases. Participants began each 24-hr fast with either a high carbohydrate/low fat/moderate protein (HC/LF) or an isocaloric low carbohydrate/high fat/moderate protein (LC/HF) shake. Metabolic indicators included subcutaneous glucose readings every 15 min throughout the study, capillary beta-hydroxybutyrate (BHB), and plasma concentrations of insulin, glucagon, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP). Measurements of these hormones took place at 0, 1, 24, and 48 h, and BHB measurements took place at 0, 1, 4, 8, 12 and 24 h.
Glucose levels were higher in the HC/LF group 15 min to 2.25 h after fast initiation (p < 0.05 for all). There was a significant condition by time interaction for BHB (F = 3.84, p < 0.01). Nutritional ketosis (BHB ≥ 0.5 mmol/L) was reached on average by 12 h in the LC/HF condition but was not reached at any point during the fast on average in the HC/LF condition. An hour after consuming the LC/HF shake insulin was 41.9% lower (t = 6.13, p < 0.01), glucagon 23.6% higher (t = -4.72, p < 0.01), GLP-1 26.8% higher (t = -5.16, p < 0.01), and GIP 34.4% higher (t = -3.41, p < 0.01) compared to the HC/LF shake.
A low carbohydrate pre-fast meal can reduce time-to-ketosis in older, sedentary, overweight adults. Those looking to improve glycemic control through fasting or time-restricted eating interventions may consider the macronutrient composition of their pre-fast meal to improve its efficacy.
本研究测量了在一组老年、久坐、超重的成年人中，禁食前一餐的宏量营养素组成对24小时禁食期间酮症发生时间及其他血糖控制代谢指标的影响。
24名年龄超过50岁、久坐不动（每周运动时间少于150分钟）且超重（BMI≥27）的成年人参与了一项随机交叉研究。这些纳入标准中的每一项都已被证明会增加患慢性病的风险。参与者在每次24小时禁食开始时，要么饮用高碳水化合物/低脂肪/适量蛋白质（HC/LF）奶昔，要么饮用等热量的低碳水化合物/高脂肪/适量蛋白质（LC/HF）奶昔。代谢指标包括在整个研究过程中每15分钟测量一次的皮下葡萄糖读数、毛细血管β-羟基丁酸（BHB），以及胰岛素、胰高血糖素、胰高血糖素样肽-1（GLP-1）和葡萄糖依赖性促胰岛素多肽（GIP）的血浆浓度。这些激素的测量在0、1、24和48小时进行，BHB的测量在0、1、4、8、12和24小时进行。
禁食开始后15分钟至2.25小时，HC/LF组的血糖水平较高（所有p值均<0.05）。BHB存在显著的时间交互作用（F = 3.84，p < 0.01）。在LC/HF条件下，平均12小时达到营养性酮症（BHB≥0.5 mmol/L），但在HC/LF条件下，禁食期间平均在任何时间点都未达到。饮用LC/HF奶昔一小时后，与HC/LF奶昔相比，胰岛素降低了41.9%（t = 6.13，p <
