Gram Research analysis shows that a new randomized controlled trial is testing whether reducing ultra-processed foods helps young adults maintain more stable blood sugar levels throughout the day. The ULTRA-CGM study will enroll 50 Korean adults aged 20 to 39 who currently get at least 25% of their daily calories from junk food, then teach half of them to eat fewer processed foods while measuring blood sugar responses using continuous glucose monitors. While results aren’t yet available, existing research shows that high ultra-processed food intake is linked to type 2 diabetes risk, and this study aims to prove whether cutting back actually improves blood sugar control in healthy young people.
A new study is testing whether eating fewer ultra-processed foods (like packaged snacks, fast food, and sugary drinks) can help young adults keep their blood sugar levels more stable. Researchers in Korea are recruiting 50 healthy young adults who eat a lot of processed foods and will teach half of them how to eat fewer of these foods while keeping their total calories the same. Using continuous glucose monitors (small devices that track blood sugar throughout the day), scientists will measure whether reducing junk food helps prevent the blood sugar spikes that happen after eating. This research matters because eating too many ultra-processed foods is linked to type 2 diabetes, and we need to know if cutting back can actually help prevent this disease in young people.
Key Statistics
A 2026 randomized controlled trial protocol published in BMJ Open will evaluate 50 Korean young adults to determine whether reducing ultra-processed foods improves postprandial glucose responses and glycaemic variability using continuous glucose monitoring.
The ULTRA-CGM trial targets young adults aged 20 to 39 years whose ultra-processed food intake comprises at least 25% of their daily energy intake, using 10-day continuous glucose monitoring periods before and after a dietary intervention.
According to Gram Research analysis of this 2026 study protocol, researchers will measure blood sugar control through multiple metrics including 2-hour incremental area under the curve, coefficient of variation, and glucose spike frequency to assess whether targeted ultra-processed food reduction improves metabolic health.
The Quick Take
- What they studied: Whether eating fewer ultra-processed foods (packaged snacks, fast food, sugary drinks) helps keep blood sugar levels more stable in young adults
- Who participated: 50 healthy Korean adults aged 20 to 39 years old who currently eat a lot of ultra-processed foods (at least 25% of their daily calories come from these foods)
- Key finding: This is a study protocol describing the research plan, not yet completed. The study will measure changes in blood sugar spikes after meals and how much blood sugar bounces around throughout the day when people reduce junk food intake
- What it means for you: If this study shows that eating less junk food helps stabilize blood sugar, it could give young adults a practical way to reduce their risk of developing type 2 diabetes. However, results won’t be available until the study is completed
The Research Details
This is a randomized controlled trial, which is one of the strongest types of research studies. Researchers will divide 50 young adults into two equal groups. One group will receive a 40-minute counseling session focused on reducing ultra-processed foods, while the other group will receive standard nutrition advice based on national dietary guidelines. Both groups will wear continuous glucose monitors (small devices attached to the skin that measure blood sugar every few minutes) for 10 days before and 10 days after their counseling session. This allows researchers to see exactly how blood sugar responds to meals before and after people change their eating habits.
The study is designed to keep things fair by having both groups maintain their normal total calorie intake and lifestyle habits. The only difference is what type of foods they eat. Researchers will track multiple measurements including blood sugar spikes after meals, how much blood sugar fluctuates throughout the day, body weight, waist size, body composition, blood pressure, and grip strength. This comprehensive approach helps researchers understand whether reducing junk food has broader health effects beyond just blood sugar control.
The study uses advanced statistical methods to analyze the continuous glucose monitoring data, which captures thousands of data points per person. This detailed information is much more precise than traditional blood tests that only measure blood sugar at one moment in time.
Most previous research on ultra-processed foods and diabetes has been observational, meaning researchers simply watched what people ate and tracked who got sick. This study is different because it actually assigns people to eat differently and measures the direct effects on their bodies. This type of evidence is much stronger for proving cause and effect. Additionally, most research on this topic has been done in older adults or people already at risk for diabetes. This study focuses on healthy young adults, which is important because preventing disease early is better than treating it later
This study has several strengths that make it reliable. First, it uses continuous glucose monitoring instead of occasional blood tests, which provides much more accurate information about how blood sugar actually behaves. Second, it’s a randomized controlled trial, which is considered the gold standard in medical research. Third, the study was approved by an institutional review board, which means independent experts reviewed it to ensure it’s ethical and scientifically sound. Fourth, it follows international guidelines for good research practices. However, the study is relatively small with only 50 participants, and it only lasts 20 days total, so results may not apply to everyone or show long-term effects
What the Results Show
This research paper is a study protocol, which means it describes the research plan before the study has been completed. Therefore, actual results are not yet available. The primary outcome the researchers will measure is the change in blood sugar spikes after meals, specifically looking at something called the 2-hour incremental area under the curve. This is a technical way of measuring how much blood sugar rises and stays elevated in the 2 hours after eating a meal.
When the study is completed, researchers will compare this measurement between the group that reduced ultra-processed foods and the group that received standard dietary advice. They will use statistical methods to determine whether any differences between the groups are real or just due to chance. The study is designed to detect meaningful improvements in blood sugar control if they exist.
Beyond the main blood sugar measurement, researchers will also examine several other important outcomes. These include glycaemic variability metrics, which measure how much blood sugar bounces around throughout the day (measured by coefficient of variation, standard deviation, and mean amplitude of glycaemic excursions). They will also track glucose spike frequency, which counts how many times blood sugar shoots up after meals. Additional measurements include time-in-range metrics (how long blood sugar stays in a healthy range), body weight, waist circumference, body composition (muscle versus fat), blood pressure, and handgrip strength. These secondary outcomes will help researchers understand whether reducing ultra-processed foods affects overall health beyond just blood sugar control
Previous research has shown that high intake of ultra-processed foods is linked to increased risk of type 2 diabetes, but most of this evidence comes from studies where researchers simply observed what people ate without changing their diet. Very few randomized controlled trials have tested whether actually reducing ultra-processed foods improves blood sugar control in healthy young adults. This study fills an important gap by providing direct evidence in a population that hasn’t been studied much. The findings will help answer whether the link between junk food and diabetes is actually causal (junk food causes diabetes) or just correlational (people who eat junk food happen to have other risk factors)
This study has several limitations to keep in mind. First, it only includes 50 participants, which is a relatively small group, so results may not apply to everyone. Second, it only lasts 20 days total, so we won’t know whether the benefits last over months or years. Third, it only includes Korean young adults, so results may differ in other age groups or populations. Fourth, the study relies on people following the dietary advice they receive, and some people may not stick with the changes. Fifth, the study doesn’t include people who already have diabetes or prediabetes, so we don’t know if results would be different for those groups. Finally, this is a study protocol describing the plan, not the actual results, so we’re waiting to see what the research actually finds
The Bottom Line
This study hasn’t been completed yet, so specific recommendations based on its results aren’t available. However, existing research already suggests that reducing ultra-processed foods is a good idea for overall health. If you eat a lot of packaged snacks, fast food, or sugary drinks, gradually replacing some of these with whole foods like fruits, vegetables, whole grains, and lean proteins is a reasonable approach. The confidence level for this general recommendation is moderate to high based on existing research, though this specific study may provide stronger evidence once completed
This research is most relevant to healthy young adults (ages 20 to 39) who eat a lot of ultra-processed foods and want to reduce their risk of developing type 2 diabetes. It’s also relevant to anyone interested in blood sugar control and metabolic health. Healthcare providers and nutritionists should pay attention to these results when they become available. People who already have type 2 diabetes or prediabetes should not rely solely on this study for guidance, as it doesn’t include those populations. Older adults should also wait for additional research, as this study focuses on young adults
Since this study hasn’t been completed yet, we don’t know when results will be available. Based on the study design, data collection should take several months, and analysis and publication could take additional months. Realistic expectations for seeing personal benefits from reducing ultra-processed foods typically range from 2 to 4 weeks for noticing changes in energy levels and digestion, though improvements in blood sugar stability may take longer to measure accurately
Frequently Asked Questions
Does eating less junk food actually help control blood sugar?
A new 2026 randomized controlled trial is testing this question in 50 young Korean adults. While results aren’t available yet, existing research shows that high ultra-processed food intake is linked to type 2 diabetes risk, suggesting that reducing these foods likely helps blood sugar control
How quickly will I see blood sugar improvements if I cut out processed foods?
Blood sugar improvements can begin within days to weeks of reducing ultra-processed foods, though the most stable changes typically appear after 2 to 4 weeks of consistent dietary changes. This upcoming study will provide more precise data on the timeline
What counts as an ultra-processed food I should avoid?
Ultra-processed foods include packaged snacks, fast food, sugary drinks, instant noodles, mass-produced baked goods, and most foods with long ingredient lists containing additives. Whole foods like fruits, vegetables, whole grains, beans, nuts, and unprocessed meats are better choices
Can reducing junk food help prevent type 2 diabetes in young adults?
Research shows that high ultra-processed food intake increases type 2 diabetes risk. This 2026 study will provide direct evidence on whether reducing these foods actually prevents blood sugar problems in healthy young adults, which could help prevent diabetes development
Do I need to count calories if I’m just cutting out processed foods?
This study keeps total calories the same while changing food types, suggesting that the type of food matters beyond just calorie count. However, whole foods are often more filling, so you may naturally eat fewer calories while feeling more satisfied
Want to Apply This Research?
- Track the percentage of daily calories coming from ultra-processed foods by logging meals for 3 to 7 days, then set a goal to reduce this percentage by 10 to 20% each week. Use the app to identify which ultra-processed foods you eat most often and find whole-food alternatives
- Start by replacing one ultra-processed food per day with a whole-food alternative. For example, swap a packaged snack bar for a piece of fruit, or replace a sugary drink with water or unsweetened tea. Make this change automatic by keeping the whole-food option visible and convenient
- Use the app to track energy levels, hunger patterns, and digestion quality weekly as you reduce ultra-processed foods. If available, use a continuous glucose monitor or periodic blood sugar testing to measure objective improvements. Monitor body weight and waist circumference monthly to track body composition changes
This article describes a research study protocol that has not yet been completed. Results are not yet available. This information is for educational purposes only and should not be used to diagnose, treat, or prevent any disease. If you have concerns about blood sugar control, diabetes risk, or dietary changes, please consult with a qualified healthcare provider or registered dietitian. This study focuses on healthy young adults and may not apply to people with existing diabetes, prediabetes, or other medical conditions. Always speak with your doctor before making significant dietary changes, especially if you take medications that affect blood sugar.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.