Caffeine is everywhere: from your coffee to your tea, and even in your favorite candy bars. And while the health benefits of controlled amounts of caffeine are numerous, from calorie-burning to alertness, there are reasons to avoid it if you have certain health problems, especially high blood pressure.
Caffeine can cause a short but dramatic increase in your blood pressure, even if you have a normal baseline blood pressure. Although it is not clear why this physiological phenomenon takes place, researchers suggest that the adrenal glands release more adrenaline in response to caffeine, which causes your blood pressure to rise. It may also cause the arteries to narrow by suppressing a hormone, hence raising the over all blood pressure.
Studies have shown that people who regularly drink caffeinated beverages have a higher average blood pressure than those who do not. It is also a common phenomenon to develop tolerance to caffeine, and so people who consume it regularly will see their blood pressures return to normal after long periods of continuous consumption.
If you have a baseline high blood pressure, try to limit your daily caffeine intake, and substitute it with other beverages. Caffeine, tea etc should not be counted with your daily consumption of water. Cutting back on caffeine is advised to be done gradually over several days to avoid headaches and fatigue.