Regular coffee contains high levels of caffeine, a stimulant known to increase blood pressure immediately. Decaffeinated coffee, on the other hand, usually contains little if any caffeine, making it much less likely to raise your blood pressure. Although caffeine can increase blood pressure, no evidence supports a link between long-term consumption of regular coffee and high blood pressure. Some evidence suggests that switching from regular to decaffeinated coffee could lead to a small decrease in blood pressure.
Coffee, Caffeine and Blood Pressure
The reason that regular coffee can cause blood pressure to rise is that it contains a substantial amount of caffeine. According to MedlinePlus, three 8-ounce cups of coffee contain approximately 250 milligrams of caffeine, which means a single cup contains upward of 80 milligrams. Caffeine, a stimulant of the central nervous system, can cause increased heart rate and lead to feelings of anxiety and nervousness. Glenn Gandelman, writing on the HealthCentral website, reports that many people use coffee as a way to deal with fatigue. But this form of self-medication can lead to further fatigue and insomnia, which stresses the body. This stress can then lead to elevated blood pressure.
Switching to Decaf
A study published in the journal "Hypertension" in 1989 examined the relationship between decaffeinated coffee and regular coffee on blood pressure and heart rate. Forty-five healthy volunteers, who normally drank 4 to 6 cups of coffee a day, were divided into groups. Members of each group drank 5 cups of regular or decaf coffee for a six-week period. The total amount of caffeine consumed per day by those in the decaffeinated group was 40 milligrams, while regular coffee drinkers received 445 milligrams of caffeine per day. The study found that adults with normal blood pressure who replaced regular coffee with decaf saw a small decrease in blood pressure.
Caffeine Levels in Decaf Coffee
Although many people probably assume that all decaf coffee doesn't contain caffeine, this isn't usually the case. A study published in 2006 in the "Journal of Analytical Toxicology" examined the caffeine content of decaffeinated coffee from popular chain coffee shops. Based on 10 samples collected from different coffee outlets, the caffeine range in decaffeinated blends was between zero and 14 milligrams per 16-ounce serving. Although these doses of caffeine are relatively low, the study notes that those sensitive to caffeine should exercise caution when drinking coffee labeled as decaffeinated.
Most of the research on coffee consumption and blood pressure focuses on regular coffee, because caffeine is the component in coffee known to affect blood pressure. Aside from those who are caffeine sensitive, decaffeinated coffee drinkers should not have to worry about increases in blood pressure. But no association exists between increased cardiovascular disease or hypertension in regular coffee drinkers. As noted in a 2008 paper published in "Vascular Health and Risk Management," "Most evidence suggests that regular intake of caffeinated coffee does not increase the risk of hypertension."