Research

Mixed

Personalized diet advice based on single or few continuous glucose monitor (CGM) measurements of duplicate meals is unreliable in adults without diabetes because within-subject glycemic variability for identical meals is similar to variability for different meals.

Do not make permanent dietary changes based on a single CGM reading of one meal. Your body's response to the exact same meal can vary significantly from day to day due to factors like sleep, stress, and activity. If you use a CGM, look for broad patterns over weeks (e.g., 'plant-based diets generally lower my glucose') rather than trying to identify specific 'bad' foods based on one spike. Reliable personalization requires aggregating many repeated measurements, not just one or two.

GoodRefutesHIGH confidence
Individual postprandial CGM responses to duplicate meals were unreliable in adults without diabetes. Personalized diet advice based on CGM measurements in adults without diabetes requires more reliable methods involving aggregated repeated measurements.
Aaron Hengist et al. · medRxiv · 2023

Why this rating

Controlled inpatient metabolic ward study with rigorous statistical analysis (ICC, Bland-Altman) on 30 participants, though limited to non-diabetic adults.

Source

Imprecision nutrition? Duplicate meals result in unreliable individual glycemic responses measured by continuous glucose monitors across four dietary patterns in adults without diabetes

Aaron Hengist et al. · medRxiv · 2023

DOI 10.1101/2023.06.14.23291406

preprint · n=30Cited 6×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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