# Data Dictionary - US Food Bioactive Content - USDA flavonoid, proanthocyanidin, isoflavone & glucosinolate databases, cleaned

**Units:** stated per column in the descriptions below (this is a relational table; columns mix units).

| column | type | description |
|---|---|---|
| `source_db` | str | Which USDA database: Flavonoids, Proanthocyanidins or Isoflavones |
| `ndb_no` | str | Legacy NDB / Standard-Reference food number (join key) |
| `food` | str | Food name / description |
| `food_group` | str | USDA food group (where mapped) |
| `compound` | str | Bioactive compound (e.g. Quercetin, Genistein, (-)-Epicatechin) |
| `compound_class` | str | Compound class / subclass (e.g. Flavonols, Isoflavones) |
| `value` | float | Amount of the compound per 100 g of edible portion |
| `unit` | str | Unit of the amount (mg) |

*Source: U.S. Department of Agriculture, Agricultural Research Service - Special-Interest bioactive databases (public domain).*