Sensitivity to coffee and subjective health

The question was whether health complaints are associated with coffee consumption and
self reported sensitivity to coffee. Participants were 89 men and 107 women, all coffee
drinkers. Questionnaires were used at 2 points of time with an interval of 3.7 years. The
correlations among coffee consumption, sensitivity and health complaints were significant
but were of low importance to health. Coffee consumption was significantly related
to intestinal complaints (r=0.15) and sensitivity to coffee with sleep-wake complaints
(r=0.30). An increase in sensitivity to coffee over almost 4 years went along with less health complaints. The interaction of coffee intake and sensitivity to coffee had no influence on subjective health. Since subjective sensitivity data were used, validation of the findings should be done with objectively measured sensitivity and caffeine levels.
The main conclusion is that self-reported coffee intake is not related to subjective health,
but claimed sensitivity is.