Social factors are discussed. For example, there are comparisons of the tea culture of England with that of Japan and comparisons of both with the coffee culture of the United States. The duality of the culture of coffee (as in coffee houses) and the culture of tea (as in tea shops, tea gardens, and afternoon tea) is emphasized and illustrated with a list of more than 30 word pairs. One word in each pair is labeled the "coffee aspect" and the other the "tea aspect." The list of coffee aspects starts with "male," "boisterous," and "bohemian" and ends with "Balzac," whereas the list of tea aspects starts with "female," "decorous," and "conventional" and ends with "Proust." Cola beverages are said not to have a long enough history to have features as well differentiated as these, but they do have distinctive associations, such as "youth, high energy, America, pop culture, and `good clean fun."' Although the authors emphasize that all these popular beverages contain the drug caffeine, the diversity of the cultures associated with the different beverages suggests that caffeine is only one factor leading to their consumption.

True to its title, the book has little to say about alcohol, but the authors do make the important point that, at least in Europe and North America and at least in the large towns, raw water was not fit to drink until late in the 19th century. The increase in tea and coffee drinking offered an alternative to the usual beverages: beer, gin, and rum. The authors credibly associate this shift with a decrease in alcohol intake, to the benefit of society.

In the second half of the book, the nature of the story changes. The urbane historical perspective gives way to more recent concerns, including a discussion of what might be called huckstering by purveyors of caffeine products. Almost the final third of the book is devoted to the chemistry, pharmacology, and medical aspects of caffeine. I do not think that in a book of this size it is possible to present enough of an understanding for readers to reach their own conclusions on adequate grounds about the health and safety aspects of caffeine, and in many instances the original sources must be scrutinized for the adequacy of the evidence. In addition, there are errors. For example, a woman is said to have had a serum caffeine concentration of almost 300 mg per milliliter, which is many times the solubility of caffeine. Readers can remain confused, they can accept the often implicit conclusions of the writers, or they can opt out and simply trust the Food and Drug Administration (FDA).

A number of minor matters follow. Pure caffeine is variously described as "highly toxic" or "extremely toxic." An agent that can be ingested in amounts of several grams with relative impunity would not customarily be considered very toxic. A number of common foods -- dry mustard, horseradish, or cayenne pepper, for instance -- would not go down well as boluses of several grams. The poison of the puffer fish, whose flesh is eaten in Japan, is highly toxic, being hazardous in quantities thousands of times smaller than ordinarily consumed quantities of caffeine.

Finally, the authors aver that the International Life Sciences Institute (ILSI) was founded to help forestall efforts to regulate caffeine. But the FDA was regulating caffeine long before the ILSI was formed. The Caffeine Technical Committee of the ILSI was formed by interested companies to sponsor research on questions on caffeine raised by the FDA and others. It is prohibited from lobbying.

Peter B. Dews, M.B., Ch.B., Ph.D.
Copyright © 2001 Massachusetts Medical Society. All rights reserved. The New England Journal of Medicine is a registered trademark of the MMS.