Food database
A food database is the set of foods and nutrition values a calorie app searches; its quality — whether entries are verified, sourced and deduplicated — matters more to logging accuracy than any feature in the app.
Every calorie app is a search box in front of a food database. The interface is what you notice; the database is what decides whether the number you log means anything.
Where the entries come from
Three sources, in descending order of trust. National composition tables — USDA FoodData Central, India's IFCT, similar bodies elsewhere — come from laboratory analysis and are the closest thing to ground truth. Manufacturer data, from labels or a product feed, is reliable for packaged food. User-submitted entries are typed in by members of the public, unverified, and make up the overwhelming majority of entries in the largest apps.
How to tell a good one
Search a common home-cooked dish. A good database returns a small number of clearly labelled entries with a stated source and a sensible serving. A poor one returns forty entries for the same dish with calorie values spanning a factor of four and no indication which is right.
Why it matters more than accuracy per se
A database of user entries is not merely imprecise, it is biased: people submitting an entry for their own food tend to enter flattering numbers, and those entries then get logged by thousands of others. Choosing between eleven versions of a roti is also the slowest part of logging, which is how databases quietly decide whether anyone keeps using the app.
Sources
- 1.FoodData Central — USDA Agricultural Research Service
- 2.Open Food Facts — Open Food Facts
Related reading
- Why two apps give the same roti different calories
Different databases, source types, raw versus cooked states and user-submitted entries. Why calorie apps disagree, and which number you should actually use.
- How to judge a calorie app's food database
Six checks that take ten minutes and tell you more than any review. Where entries come from, why duplicates matter, and what a good result looks like.
- How to choose a calorie tracking app that sticks
The database decides accuracy, speed decides whether you keep using it, and export decides whether you can leave. Everything else is decoration.
- Logging food by voice: what it actually fixes
The slow part of tracking is choosing between database entries, not typing. Why speaking a meal removes that step, and where voice logging still fails.