Effects of Ultra-processed Food Reduction Intervention on Postprandial Glucose and Glycemic Variability in Korean Young Adults: Study Protocol for the ULTRA-CGM Randomized Controlled Trial
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 50
- 试验地点
- 1
- 主要终点
- Change in postprandial glucose responses
研究概览
简要总结
The goal of this trial is to investigate whether reduction in ultra-processed food intake through dietary counseling and education can improve postprandial glucose responses and glycemic variability compared with a usual diet in young, healthy Korean adults aged 20-30 years. The main questions it aims to answer are:
- Does reducing ultra-processed food intake, while maintaining total energy intake and usual lifestyle behaviors, improve postprandial glucose and lower glycemic variability in healthy adults without diabetes?
Participants will:
- Undergo the 10-day pre-intervention monitoring period, during which each participant will wear a continuous glucose monitoring (CGM) device and concurrently report their daily dietary intakes (all food and beverage consumption) and other lifestyle behaviors (sleep, smoking, physical activity)
- After the 10-day pre-intervention monitoring period, participants will be randomized to either intervention or control group
- Intervention group: Participants will visit the research site to receive dietitian-led one-on-one nutrition education and personalized dietary counseling targeting reduction of ultra-processed food intake. Personalized diet counseling will be provided by study dietitian based on participant's records of dietary intakes during the 10-day pre-intervention monitoring period.
- Control group: Participants will receive dietitian-led nutrition education and personalized dietary counseling based on the national dietary guidelines.
- After the intervention, participants will undergo the 10-day post-intervention monitoring period, during which participants will wear a new CGM device for an additional 10 days and continue daily reporting of dietary intakes (all food and beverage consumptions) and lifestyle behaviors (sleep, smoking, physical activity).
详细描述
The Ultra-Processed Food Reduction Intervention and Continuous Glucose Monitoring (ULTRA-CGM) trial is a parallel, two-arm randomized controlled trial designed to evaluate the effects of a ultra-processed food (UPF)-reducing dietary intervention on postprandial glucose responses and glycemic variability in young Korean adults (aged 20-39 years) using CGM devices. Participants will be randomly assigned to either a UPF-reducing intervention group or a control group maintaining their usual diet. We hypothesize that receiving the UPF-reducing dietary intervention will improve postprandial glucose responses and reduce glycemic variability compared with participants receiving standard dietary counseling based on national guidelines. The findings from this trial may provide experimental evidence on the metabolic effects of reducing UPF consumption and inform dietary strategies for diabetes prevention among younger adults.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
Participants and outcome assessors were blinded to group allocation. The study dietitian responsible for delivering the intervention was not blinded; however, allocation was concealed until the time of intervention delivery.
入排标准
- 年龄范围
- 20 Years 至 39 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Korean adults aged 20-39 years
- •Not currently pregnant
- •No personal history of diabetes or other glucose-related conditions
- •Consume ≥25% of daily energy intake from UPFs, as assessed by an online, self-administered semi-quantitative screening food frequency questionnaire (FFQ)
- •No restriction on wearing a CGM device
- •No increased risk of bleeding
- •No prior adverse reaction to CGM devices
- •Willingness to participate in follow-up assessments
排除标准
- •Unable to maintain continuous follow-up during the study period (e.g., due to special plans such as traveling)
- •Planning to follow a special or restrictive diet (e.g., for weight loss) during the study period
研究组 & 干预措施
Intervention group
Participants will be randomly assigned to the intervention group using block randomization with a 1:1 allocation ratio.
干预措施: 40-minute one-on-one dietary counseling and nutrition education aimed at reducing ultra-processed food consumption (Behavioral)
Control group
Participants will be randomly assigned to the control group using block randomization with a 1:1 allocation ratio.
干预措施: Standard dietary counseling and nutrition education based on national guidelines (Behavioral)
结局指标
主要结局
Change in postprandial glucose responses
时间窗: Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention)
The primary outcome of this study is the change in postprandial glucose responses from the baseline monitoring period to the post-intervention monitoring period. Postprandial glucose responses are assessed using CGM and quantified as the incremental area under the curve (iAUC) over 2 hours following each meal. Higher iAUC values indicate greater postprandial glucose excursions. For each meal, iAUC is calculated as the area under the curve above the baseline level over the 2-hour postprandial period, using the trapezoidal rule. The baseline glucose level is defined as the mean glucose value in the 5 minutes immediately preceding meal consumption. For overlapping meals, the iAUC for the first meal is calculated from its start until 2 hours after, and overlapping periods are excluded from subsequent meals' iAUC to ensure each glucose excursion is counted once.
Postprandial glucose
时间窗: Two hours after the start of each meal, throughout the 10-days of intervention period.
Outcome measures will be collected using a continuous glucose monitoring device (Dexcom G7 , Dexcom Inc., San Diego, CA, USA). All participants will wear a continuous glucose monitoring device during both the 10-day pre-intervention monitoring period and 10-day post-intervention monitoring period to evaluate the differences in postprandial glucose levels and glycemic variability. To ensure the validity of continuous glucose monitoring readings, each device will be calibrated using a single-time finger-prick blood glucose meter. Postprandial glucose (mg/dL) will be measured using continuous glucose monitoring data captured two hours after the start of each meal, with mealtimes reported via a lifestyle log application.
次要结局
- Change in coefficient of variation (CV)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in standard deviation (mg/dL)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in mean amplitude of glycemic excursions (MAGE)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in glucose spike frequency(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in waist circumference (cm)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in time-in-range (%)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in time-in-tight-range (%)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in time-above-range (%)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in time-below-range (%)(Change in mean values from the baseline monitoring period (10-day period before the intervention) to the post-intervention monitoring period (10-day period immediately following the intervention))
- Change in body weight (kg)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in fat mass (kg)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in muscle mass (kg)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in percentage of body fat (%)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in blood pressure measurements (mmHg)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Change in handgrip strength (kg)(Change from study enrollment (day 1) to study completion (day 23; 10 days after the intervention))
- Coefficient of variation (CV)(During the 10-day intervention period.)
- Standard Deviation (SD)(During the 10-day intervention period.)
- Time in range 70-180 mg/dL (TIR 70-180, %)(During the 10-day intervention period.)
- Time in range 90-126 mg/dL (TIR 90-126, %)(During the 10-day intervention period.)
- Time above range >126 mg/dL (TAR126, %)(During the 10-day intervention period.)
- Time below range <90 mg/dL (TBR90, %)(During the 10-day intervention period)
研究者
Hannah Oh
Associate Professor
Korea University