Caffeine is a stimulant that can increase your energy and alertness. But it can also activate the central nervous system, contribute to jitters and elevate your heart rate. Your blood pressure can also be affected by the drug -- although the effects aren't permanent, caffeine consumption can cause a spike in your blood pressure that lasts several hours. Coffee is a potent source of caffeine and therefore can contribute to a temporary increase in your blood pressure.
Blood Pressure Risks
High blood pressure increases the force against the walls of your blood vessels. This can thicken and harden your arteries and increase your risk of many serious health conditions. A heart attack or stroke is possible, as are aneurysms and even heart failure. Thickening in the blood vessels of your eyes can cause vision loss, according to the Mayo Clinic. High blood pressure can also affect brain function and inhibit your ability to recall memories or understand concepts.
Caffeine's Effects
The exact way caffeine increases your blood pressure is unknown. According to MayoClinic.com, two to three cups of coffee can raise blood pressure considerably and keep it elevated until the caffeine wears off several hours later. One theory suggests caffeine blocks a hormone used by the body to dilate the arteries. Caffeine may also increase the adrenaline released from your adrenal gland, boosting blood pressure. But all of these effects are short-term -- regular coffee drinkers do not experience higher average blood pressure than people who do not drink caffeine.
Reducing Caffeine Consumption
You should also limit caffeine consumption to 200 mg daily if you already suffer from high blood pressure. If you need to reduce or end your intake of caffeine, lower your consumption gradually over several days or even a week -- do this to avoid the withdrawal headaches that accompany giving up caffeine abruptly.
Considerations
Many other factors can influence your blood pressure readings. Although it is wise to keep track of your caffeine use, you also need to watch other potential factors that may cause an increase in your blood pressure. Your blood pressure risk increases with age and can be affected by your ethnicity -- high blood pressure is far more common in blacks than whites. Your weight, activity level, tobacco and alcohol use, stress, family history and certain nutritional deficiencies can also increase your risk of developing high blood pressure.
