Estimate the blood sugar rise from a meal, then let the app learn from your own readings to get more accurate over time.
This is the part that actually reflects your own body — it's learned from your logged before/after readings, not assumptions.
GI, GL, and carb values are from the 2021 International Tables of Glycemic Index and Glycemic Load (Atkinson et al., Am J Clin Nutr, doi:10.1093/ajcn/nqac031) — the standard clinically-tested reference set, covering ~1,977 foods that have actually been lab-tested in humans. Fiber/fat/protein figures are category-level estimates, not measured per item, used only to model how they blunt a spike. Foods outside this list aren't guessed at — they simply won't appear in search.
Everything you enter is stored only on this device (browser local storage). Nothing is sent anywhere.