| Content (millions of kg) | Methylxanthines consumedb (millions of kg) | Daily per-caput consumption (mg) | Percentage total consumed | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Caffeine | Theophylline | Theobromine | Caffeine | Theophylline | Theobromine | Caffeine | Theophylline | Theobromine | Caffeine | Theophylline | Theobromine | |
| Coffee | 15.23 | 11.65 | 140.7 | 72.3 | ||||||||
| Tea | 2.72 | 0.03 | 0.15 | 1.85 | 0.01 | 0.06 | 22.3 | 0.14 | 0.75 | 11.5 | 100 | 1.9 |
| Cocoa | 0.55 | 4.14 | 0.42 | 3.17 | 5.1 | 38.3 | 2.6 | 98.1 | ||||
| Kola nut and other | 0.05 | 0.04 | 0.4 | 0.2 | ||||||||
| Caffeine | 2.86 | 2.16 | 26.1 | 13.4 | ||||||||
| Total (each methylxanthine) | 21.41 | 0.03 | 4.29 | 16.12 | 0.01 | 3.23 | 194.6 | 0.14 | 39.05 | 100 | 100 | 100 |
| Total (all methylxanthines) | 25.73 | 19.36 | 233.79 | 83.2 | 0.1 | 16.7 | ||||||
From Hirsh (1984)
Preparation and extraction losses were estimated as 10% for caffeine from coffee; 25%, 50% and 50% for caffeine, theophylline and theobromine, respectively, from tea; 10% for both caffeine and theobromine from cocoa; 10% for caffeine from kola nut; and 10% for caffeine alkaloid. In each case, an additional loss totalling 15% was assumed as waste from all causes.
From: Caffeine
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