PT  - JOURNAL ARTICLE
AU  - Gilbert, R. M.
AU  - Marshman, J. A.
AU  - Schwieder, M.
AU  - Berg, R.
TI  - Caffeine content of beverages as consumed
DP  - 1976 Feb 07
TA  - Canadian Medical Association Journal
PG  - 205--208
VI  - 114
IP  - 3
4099  - http://www.cmaj.ca/content/114/3/205.short
4100  - http://www.cmaj.ca/content/114/3/205.full
SO  - CMAJ1976 Feb 07; 114
AB  - Quantitative analysis of beverages prepared at home by staff of the Addiction Research Foundation revealed a lower and much more variable caffeine content of both tea and coffee than had been reported in earlier studies, most of which were based on analysis of laboratory-prepared beverages. Median caffeine concentration of 37 home-prepared samples of tea was 27 mg per cup (range, 8 to 91 mg); for 46 coffee samples the median concentration was 74 mg per cup (range, 29 to 176 mg). If tea and coffee as drunk contain less caffeine than generally supposed, the potency of caffeine may be greater than commonly realized, as may the relative caffeine content of certain commercial preparations, including chocolate and colas. The substantial variation in caffeine content emphasizes the need to establish actual caffeine intake in clinical, epidemiologic and experimental investigations of caffeine effects.