Coffee, caffeine and hemostasis: results from two randomized studies

Atherosclerosis. 1990 Aug;83(2-3):249-55. doi: 10.1016/0021-9150(90)90170-n.


The influence of coffee and caffeine consumption on hemostatic factors was studied in 2 randomized trials. Both studies were conducted in young, healthy adults. In the first study, 107 participants were randomly allocated to one or 3 intervention groups, drinking filtered coffee, boiled coffee or no coffee at all, respectively, for a period of 9 weeks. In the second study, 69 subjects received either 4-6 tablets containing 75 mg caffeine or the same amount of placebo tablets, while using decaffeinated coffee. In this double-blind study caffeine intake from any other source was not allowed. Blood samples for hemostatic factors were obtained at baseline and after 9 weeks of intervention. The findings indicate no effect of coffee consumption on fibrinogen, clotting factor VII activity, factor VIII antigen, protein C and protein S and also no effect of caffeine consumption on fibrinogen and factor VII activity.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Caffeine / adverse effects*
  • Coffee / adverse effects*
  • Cohort Studies
  • Dose-Response Relationship, Drug
  • Factor VII / metabolism
  • Factor VIII / metabolism
  • Fibrinogen / metabolism
  • Glycoproteins / metabolism
  • Hemostasis / drug effects*
  • Humans
  • Netherlands
  • Protein C / metabolism
  • Protein S


  • Coffee
  • Glycoproteins
  • Protein C
  • Protein S
  • Caffeine
  • Factor VII
  • Factor VIII
  • Fibrinogen