# Data Dictionary - US Food Nutrition Composition - USDA FoodData Central (Foundation + SR Legacy + FNDDS), full nutrient panels

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

| column | type | description |
|---|---|---|
| `fdc_id` | int | FoodData Central food id (primary key with nutrient) |
| `ndb_number` | str | Legacy NDB / Standard-Reference number (where assigned) |
| `description` | str | Food name / description |
| `food_category` | str | USDA food category (or WWEIA survey category for FNDDS foods) |
| `data_type` | str | Source bundle: foundation_food, sr_legacy_food or survey_fndds_food |
| `nutrient` | str | Nutrient name (e.g. Protein, Energy, Calcium, Ca) |
| `nutrient_unit` | str | Unit of the amount (G, MG, UG, KCAL, …) |
| `amount` | float | Amount of the nutrient per 100 g of edible portion |
| `nutrient_rank` | float | USDA display/sort rank for the nutrient |

*Source: U.S. Department of Agriculture, FoodData Central (public domain).*