Dietary Protein Sources and Glycemic Variability

This goal of trial is to evaluate the effects of plant-based vs. animal-based diets on glycemic variability in overweight or obese adults through a 3-week dietary intervention. The main question it aims to answer is: Will a plant-based diet be able to reduce glycemic variability in overweight or obese adults compared with an animal-based diet? Participants will strictly follow a designated plant-based or animal-based dietary regimen throughout the duration of the 3-week study. They will wear a Continuous Glucose Monitor (CGM) throughout the study, engage in weekly clinical assessments, and record their daily dietary intake.

Diabetes stands as one of the most rapidly escalating health challenges of the 21st century. Type 2 diabetes, which represents over 90% of all diagnosed cases, is the predominant form of the disease, with obesity and being overweight identified as key risk factors. The mainstay of prevention and management for Type 2 diabetes continues to be dietary intervention and nutritional therapy. Current dietary strategies for Type 2 diabetes focus predominantly on the regulation of fat and carbohydrate intake, while the influence and underlying mechanisms of dietary protein on glucose metabolism are not yet fully comprehended. A randomized, open-label, parallel-controlled clinical trial, by strictly controlling the source of protein, will be performed to evaluate the effects of a plant-based diet on glycemic variability and other metabolic outcomes in individuals who are overweight or obese, in comparison to an animal-based diet. Eligible participants will be randomly allocated in a 1:1 ratio to either the plant-based or animal-based diet group for a 3-week intervention. During the intervention, participants in the plant-based diet group will receive three daily meals for three weeks.Of the energy of each meal, 60% is from carbohydrates, 15% from plant protein, and 25% from fat. The primary sources of plant protein will include soybeans, lentils, nuts, grains, and seaweed. Conversely, the animal-based diet group will also be provided with three daily meals for three weeks, with the same caloric distribution, but sourcing their protein from animal products such as poultry, beef, pork, fish, eggs, and dairy. Participants are required to cooperate in completing the following tasks: 1. Daily dietary record: Participants are to meticulously track their daily food consumption. 2. Continuous 24-hour glucose monitoring and data logging: Subjects are to undergo continuous monitoring of blood glucose levels throughout a 24-hour period, with all data accurately recorded. 3. Physical examination: This will include assessments of height, weight, waist-to-hip circumference ratio, blood pressure, and body composition. 4. Biological sample collection: Samples to be collected include blood, urine, and stool. The timing for physical examinations and biological sample collections is scheduled as follows: Day 5 ± 2 of the introduction phase, Week 1 ± 2 days of the intervention phase, Week 2 ± 2 days of the intervention phase, and Week 3 ± 2 days of the intervention phase. Dietary and health counseling will be consistently available throughout the study to provide participants with continuous support and guidance.