Coffee drinking seems to increase the risk of requiring antihypertensive drug treatment.
Researchers determined daily coffee consumption via questionnaire in 24,710 Finnish subjects and observed them prospectively over 13 years. They concluded that coffee drinking was associated with a slightly increased risk of requiring antihypertensive treatment. This risk was higher in subjects with low-to-moderate coffee intakes (2 to 8 cups each day), but no effect was seen for those who drank only one cup daily. The authors also noted that coffee consumption is associated with a reduced risk of type 2 diabetes and concluded that the relationship between coffee consumption and cardiovascular disease is likely to be complicated. (Coffee consumption and the incidence of antihypertensive drug treatment in Finnish men and women. Am J Clin Nutr. 2007 Aug;86(2):457-64).