| Tea Samples/Food Samples | Caffeine Level (%) |
| Soft Drink | 0.02 [13, 18] |
| Chocolate | 0.074 [13, 18] |
| Green tea | 3.11 [13, 18] |
| Black tea | 3.57 [13, 18] |
| Earl grey tea | 4.27 [13, 18] |
| Mambila beverage tea | 0.040 [1] |
| Chinese green tea | 0.023 [1] |
| White tea | 88 [5] |
| Red tea | 60 [5] |