Sources and methodology
GutLens brings food and symptom records together as reviewable estimates and patterns. This page explains where nutrition information comes from, how screening and comparisons work, and what they cannot tell you.
Nutrition data sources
GutLens uses several food-data services for searches: USDA FoodData Central for food-name or description lookups; Open Food Facts for barcode and product lookups; Edamam for food names or natural-language descriptions; and CalorieNinjas for natural-language meal descriptions.
Nutrition values come from those sources or from a deterministic per-gram calculation using the selected food and portion. They are never invented by a language model. Estimates and matches remain reviewable and editable.
How meal estimates work
You can enter a meal in natural language, scan a barcode, search for a product, or review a photo. Text and product searches are matched against food data; ambiguous or low-confidence matches are held for your confirmation or editing.
A photo estimates food components and portion gram ranges; it does not estimate calories directly. Nutrition is calculated from grounded food data after the portion is confirmed. Unresolved or low-confidence matches wait for confirmation rather than being saved as certain.
How FODMAP screening works
GutLens screens ingredient names, additive tags, and known FODMAP-relevant compounds such as sorbitol. This is an ingredient-level screen, not a lab-verified classification of a serving size. When information is insufficient or confidence is low, the result is labelled “Not enough information” rather than guessed.
How patterns are calculated
GutLens compares how often a symptom follows a food with your own baseline symptom rate on days without that food. Confidence tiers rise only after repeated exposures; one unusual day is not enough. A displayed pattern is always a temporal association, not proof that a food caused a symptom.
Limits
GutLens is not a diagnosis and is not a substitute for a doctor or registered dietitian. Food matches, portions, nutrition estimates, screening, and observed patterns can be wrong. Entries stay editable so you can review and correct them.
Further reading
- USDA FoodData Central
- Open Food Facts
- Monash University: FODMAPs and IBS
- NIDDK: Irritable Bowel Syndrome
GutLens is not affiliated with or endorsed by these organizations or services.