| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Commelina benghalensis | Leaf | 95000.0 | 688400.0 | 0.6 | CRC Handbook of Medicinal Herbs and/or CRC Handbook of Proximate Analyses |
| Corchorus olitorius | Leaf | 58000.0 | 633000.0 | 0.2 | * |
| Coriandrum sativum | Leaf | 73000.0 | 589000.0 | -0.2 | CRC Handbook of Medicinal Herbs and/or CRC Handbook of Proximate Analyses |
| Coriandrum sativum | Fruit | 549900.0 | 603240.0 | -1.0 | USDA's Ag Handbook 8 and sequelae) |
| Cornus florida | Seed | -- | 733000.0 | 0.8 | * |
| Corylus avellana | Seed | 177000.0 | 229000.0 | -1.2 | * |
| Crataegus laevigata | Fruit | 256122.0 | 918000.0 | 0.7 | * |
| Crataegus rhipidophylla | Fruit | -- | 918000.0 | 0.7 | Pedersen, M. 1987. Nutritional Herbology. Pederson Publishing. Bountiful, Utah. 377 pp. |
| Crescentia alata | Seed | 229000.0 | 237000.0 | -1.1 | * |
| Crocus sativus | Silk Stigma Style | 436400.0 | 573000.0 | -1.0 | * |
| Cucumis melo | Fruit | 83600.0 | 818026.0 | 0.2 | USDA's Ag Handbook 8 and sequelae) |
| Cucumis sativus | Fruit | 29100.0 | 736709.0 | -0.2 | * |
| Cucurbita foetidissima | Leaf | -- | 492000.0 | -1.0 | CRC Handbook of Medicinal Herbs and/or CRC Handbook of Proximate Analyses |
| Cucurbita spp | Fruit | 43500.0 | 688300.0 | -0.5 | * |
| Cucurbita pepo | Flower | 32800.0 | 676290.0 | 0.1 | USDA's Ag Handbook 8 and sequelae) |
| Cucurbita pepo | Seed | 60000.0 | 191341.0 | -1.3 | * |
| Cucurbita pepo | Fruit | 65000.0 | 773809.0 | -0.0 | USDA's Ag Handbook 8 and sequelae) |
| Cuminum cyminum | Seed | 442000.0 | 570000.0 | 0.2 | * |
| Cuminum cyminum | Fruit | 442000.0 | 570000.0 | -1.1 | * |
| Curcuma longa | Rhizome | 79000.0 | 829000.0 | 0.7 | CRC Handbook of Medicinal Herbs and/or CRC Handbook of Proximate Analyses |