The same food can spike blood glucose dramatically in one person while barely affecting another. Research by Zeevi showed variation between people is larger than variation from food to food. Factors include genetics, insulin resistance, body composition, gut microbiome, sleep, stress, and meal timing. Glycemic index tables are averages — useful but not necessarily accurate for you.
This companion covers factors influencing response, the landmark research, and why self-observation through glucose monitoring matters. (3 min read)