Continuous Glucose Monitoring Not Just for Diabetes Anymore

Miriam E. Tucker, for Medscape

October 19, 2022

Researchers published the study covered in this summary on Research Square as a preprint that has not yet been peer-reviewed.

Key Takeaways

  • Continuous glucose monitoring (CGM) reliably tracked postprandial glucose profiles in people without diabetes and appeared to reflect the nutritional content of different meals as well as the sequence of meals that contained standardized nutritional content, findings that suggest the potential use of CGM in people without diabetes.

Why This Matters

  • Development of low-cost and easy-to-use CGM devices has made the technology potentially attractive for individuals without diabetes as a device aimed at improving health and lifestyle.

  • Previous studies have not specifically examined CGM data on postprandial glucose excursions in individuals without diabetes while accounting for the effects of meal order and nutritional composition of meals.

  • The findings suggest that CGM can be a valuable tool for people without diabetes to assess the impact of their eating behaviors.

  • Awareness of a person's glucose responses to different foods and meal patterns might, for example, help people with metabolic disorders adjust their nutritional behavior to better optimize their glucose profiles.

Study Design

  • On two consecutive days, 36 adults without diabetes at a single center in Germany received standardized test meals for breakfast and lunch followed by a free-choice dinner from a buffet.

  • The two test meals contained equal amounts of carbohydrates (50 g) with different absorption characteristics and fat and protein content for meals that either produced fast or slow glucose absorption.

  • The fast test meals mainly consisted of simple carbohydrates and a low content of fat and protein. The slow test meals were composed of complex carbohydrates, high fat content, and slightly higher protein content than fast test meals.

  • Participants consumed a fast test meal for breakfast and a slow test meal at lunch, and the next day, a slow test-meal breakfast followed by a fast test-meal lunch. 

Key Results

  • Study participants were an average of 24 years old and 58% were women. Average body mass index was 23.8 kg/m2.

  • Median fasting glucose values were similar on both days.

  • The highest postprandial glucose levels occurred after a fast test meal. The area under the curve for glucose after eating a fast test meal was greatest within the first hours followed by a rapid decline. Meals with rapidly absorbed carbohydrates and low fiber content induced rapid increases in postprandial glucose.

  • Slow test meals caused a low and prolonged postprandial glucose increase. By 5 hours after a slow test meal, glucose values had not returned to baseline. Consuming a slow test meal for lunch induced a higher glucose increase than when it was consumed for breakfast.

  • In addition to the glycemic effects of individual meals, meal sequence also seemed to matter. Glycemic trajectories differed after a fast test meal for breakfast and a slow test meal for lunch compared with the opposite order even though the participants ate the same test meals and had similar pre-meal glucose levels.

  • Feelings of satiety before dinner were lower when participants ate a fast test meal for lunch and their energy intake during dinner was also consistently higher. In contrast, satiety was higher before lunch when participants had eaten a slow test meal at breakfast. Slow test meals produced a feeling of satiety for a longer time and decreased the rate of energy intake at the subsequent meal.


  • Test meals had a specific composition that was different from usual meals.

  • The study relied on first-generation, intermittent-scanning CGM devices, which may not be as accurate as current-generation devices.

  • The number of study participants was relatively small.


  • The study received no commercial funding.

  • One of the authors has reported receiving funding and consulting fees from several companies. The other authors have reported no relevant financial relationships.

This is a summary of a preprint research study "Suitability of continuous glucose monitoring in healthy subjects to detect effects of meal sequences and nutritional content of meals on postprandial glycemic responses," written by researchers at the Institute of Diabetes Technology, Research and Development of the University of Ulm, Germany, on Research Square provided to you by Medscape. The study has not yet been peer-reviewed. The full text of the study can be found on


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