Abstinence from coffee leads to a fall in blood pressure.

The long-term effects of coffee use on blood pressure and the effects of two common brewing methods were studied for 12 weeks in 107 young normotensives. The subjects were randomly assigned to one of three groups, receiving either (1) 4-6 cups of filtered coffee per day, (2) 4-6 cups of boiled coffee per day, or (3) no coffee for a period of 9 weeks. During the 9 weeks of abstinence, systolic and diastolic blood pressure decreased. The fall in systolic blood pressure amounted to 4.9 mmHg, compared with the filter group (P = 0.02). There was no difference with either brewing method. Our findings suggest that abstinence from coffee may reduce blood pressure in young normotensive subjects.