Dear Alice,

Does caffeine raise your blood pressure?

Dear Reader,

You raise a good question! In people with normal blood pressure, it appears that caffeine may cause a temporary increase in blood pressure. The specific mechanism behind this is unknown. However, some researchers have hypothesized that caffeine either blocks a hormone that helps keep your arteries widened or causes your adrenal glands to release more adrenaline, which results in increased blood pressure. Some folks develop a tolerance to caffeine, and it doesn’t result in a long-term change in blood pressure. Though there’s no evidence to suggest that caffeine can cause high blood pressure (HBP), it’s recommended that those who’ve already been diagnosed with HBP (also called hypertension) temper their caffeine consumption.

For individuals with high-normal blood pressure or diagnosed hypertension, caffeine seems to raise their levels to a much greater degree than those with normal readings. It’s also been noted that caffeine has a stronger blood pressure increasing effect in men who are overweight or older than 70 years old. To mitigate this effect, it’s recommended that these folks try to avoid caffeine.

For reference, classification of blood pressure is as follows (in mmHg or millimeters of mercury):

  • Normal — systolic: less than 120; and diastolic: less than 80
  • Prehypertension — systolic: 120 to 139; or diastolic 80 to 89
  • Stage 1 HBP — systolic: 140 to 159; or diastolic 90 to 99
  • Stage 2 HBP — systolic: more than 160; or diastolic more than 100

For your average joe, it's probably a good idea to refrain from ingesting caffeine just before a blood pressure test. It could trigger a temporary rise, resulting in an inaccurate reading. Coffee may be the most likely culprit, but chocolate, soda, and energy drinks have varying amounts of caffeine as well. For those who aren’t sure whether caffeine affects their blood pressure, try measuring your blood pressure before your next cup of coffee (or caffeinated food stuff) and again within 30 to 120 minutes afterward. If your blood pressure goes up by five to ten points in that period of time, it may indicate sensitivity to the effects of caffeine.

Cutting out caffeine may be a good choice for some, but it’s recommended to do so gradually to avoid experiencing withdrawal symptoms. Can’t give up good ol' java? Decaffeinated coffee may serve as a suitable substitute, with a typical caffeine content of about five milligrams (mg) per eight ounce (oz.) cup (versus around 135 mg of caffeine for the regular brew). Hot cocoa is a choice that also contains approximately five mg of caffeine per eight oz. mug (with an added bonus of calcium and er… chocolate!) for those seeking an alternative beverage altogether. There are also herbal teas, which contain no caffeine and are available in a variety of flavors. A health foods store may also have a few additional offerings, including non-caffeinated herbal or grain beverages.


Submit a new response

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.

Vertical Tabs