Psychotropic effects of caffeine in man. III. A questionnaire survey of coffee drinking and its effects in a group of housewives

By means of a questionnaire, information was gathered about coffee drinking and its effects in 239 young housewives. The group was divided into roughly equal parts with respect to daily coffee consumption: abstainers, light users (1 to 2 cups); moderate users (3 to 4 cups); and heavy users (5 or more cups). The respondents were asked why they drink coffee in the morning, what behavioral changes it produces, and what effects would ensue if morning coffee were omitted. They were also asked if coffee makes them wakeful at night. The results indicate substantial differences in the responses correlated with the extent of coffee use. Heavy users reported less wakefulness caused by coffee at night and less nervousness caused by coffee in the morning as compared with light users. On the other hand, heavy users reported more of the desirable stimulant and euphoriant effects than did light users. Heavy users also described a characteristic set of dysphoric symptoms attributed to omission of morning coffee: irritability, inability to work effectively, nervousness, restlessness, lethargy, and headache. The validity of these results was confirmed in an experimental study on some of the same subjects reported in the accompanying paper.