Ultra-processed Food-reducing Intervention and Continuous Glucose Monitoring

Summary

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).

Conditions

• Postprandial Glucose
• Glucose Levels
• Hyperglycemias

Interventions

BEHAVIORAL

40-minute one-on-one dietary counseling and nutrition education aimed at reducing ultra-processed food consumption

Participants assigned to the intervention group receive a 40-minute one-on-one nutrition education session and personalized dietary counseling delivered by the study dietitian. The goals of these sessions are to reduce UPF consumption while maintaining total energy intake and usual lifestyle behaviors. All sessions follow a standardized protocol to ensure consistent delivery of the intervention. The study dietitian delivering the intervention receives training on the standardized protocol prior to participant enrollment.

BEHAVIORAL

Standard dietary counseling and nutrition education based on national guidelines

Participants assigned to the control group are also provided with a 40-minute one-on-one nutrition education session and personalized dietary counseling, but with different objectives. During these sessions, the national dietary guidelines are introduced using an educational leaflet distributed by the Ministry of Health and Welfare. The education session and counseling provided to the control group do not include any information on UPFs. After completion of the study, participants in the control group are provided with the same nutrition education materials on UPF reduction that are used in the intervention group.

Sponsors & Collaborators

• Korean Society of Cardiometabolic Syndrome (funder)

  collaborator UNKNOWN

• Korea University

  lead OTHER

Principal Investigators

• Hannah Oh, ScD · Department of Health Policy and Management, Korea University, Seoul, Republic of Korea

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

20 Years

Max Age

39 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-10-11

Primary Completion

2026-08-31

Completion

2026-08-31

Countries

• South Korea

Study Locations