Every time you go to the doctor, a technician wearing a white lab-coat asks you to sit down, puts an arm cuff on your arm, and inflates it to measure your blood pressure. Then she announces the result, for example, “133 over 70” (133/70).
What is blood pressure exactly?
Maybe you’ve wondered: what is blood pressure? And why do they always measure it when you go to the doctor, and what on earth does it mean to say something like “133 over 70”? Is that normal? Too high? Not high enough?
As you no doubt recall from your school days, the circulatory system— consisting of the heart and the blood vessels—is the body’s transit system. It carries essential supplies—such as oxygen, nutrients, and vitamins—to the organs so they can do their jobs. And it carries away the wastes.
To move your blood around, your heart beats about 100,000 times per day. Blood pressure is a measure of how strongly it beats and the size of the blood vessels the blood is moving through.
It is measured in millimeters of mercury at two points:
when the heart beats (the systolic pressure) and
when the heart is between beats (the diastolic pressure).
So if your blood pressure is 133/70, 133 is your systolic pressure and 70 is your diastolic pressure.
How high is too high?
Generally, if your systolic blood pressure is 140 or higher or your diastolic is 90 or higher, you have high blood pressure (or hypertension).
If your systolic blood pressure is between 120 and 139 or your diastolic is between 80 and 89, you have pre-hypertension, which means that you’re at risk of developing high blood pressure.
Why you should measure your own blood pressure
- High blood pressure puts you at risk of a heart attack, a stroke, or kidney disease.
- There are generally no symptoms of high blood pressure, so you won’t be aware that you’re at risk.
- Most people have only one or two medical exams a year.
- Often when a technician measures your blood pressure in your doctor’s office, the number is abnormally high. This happens so often, in fact, that there’s a name for it: it’s called “white-coat hypertension.”
- High blood pressure is very common. In the U.S. more than half of all Americans aged 60 or older have it. Those who don’t have it yet are likely to develop it later.
- Monitoring your own blood pressure is one way to take personal responsibility for your own health.
- It’s easy to do and—if you have high blood pressure and are being treated for it by medication or other means—the results show how well the treatment is working.
What’s age got to do with it?
In the U.S. increasing blood pressure is often regarded as an inevitable part of natural aging, but, as discussed here, some studies show that that’s not the case.
How do you measure your blood pressure?
You can buy a home blood pressure monitor with an inflatable arm cuff and a monitor with a digital screen for about $60 to $70. One source (Johns Hopkins Health Alert, dated March 9, 2010) recommends that you monitor your blood pressure at home if you know or suspect that you have high blood pressure and that you
…receive instruction on its use from a healthcare professional.
With all due respect I find that to use a home blood pressure monitor, all you need is the ability to read and to tell which joint is your elbow and which is your shoulder. (It does makes sense, however, to take your blood pressure monitor with you to your doctor’s office once a year to check its accuracy.)
Monitoring my own blood pressure
I monitor my blood pressure for several reasons. One is that I have Type 2 diabetes which increases my risk of a heart attack or a stroke. Another is that high blood pressure also increases those risks.
Although I have high blood pressure, it’s well controlled by a combination of medication, diet, and exercise. I just measure it from time to time to see how I’m doing.
For the last few weeks, I been taking some blood pressure measurements in the morning (after coffee but before breakfast). Here are the results:
3/19 116/69 3/29 123/64 3/21 115/59 3/22 119/66 3/24 116/72 3/27 120/65 3/29 123/64 4/06 102/63; * 4/14 114/61 4/17 109/64.
* This one prompted my BF to claim that he’d seen corpses with higher blood pressure.
Does blood pressure vary during the day?
My number are as low as they are because—for one thing—I took them early in the morning. According to Sheldon G. Sheps, M.D., (Mayo Clinic emeritus hypertension specialist)
Blood pressure has a daily pattern. Blood pressure is normally lower at night while you’re sleeping and when you first wake up. As soon as you get out of bed, it begins to rise. Your blood pressure continues to rise during the day, usually peaking in the middle of the afternoon. Then in the late afternoon and evening, your blood pressure begins dropping again.
How about you? Is your blood pressure higher than should be? How do you control it? Do you monitor it yourself? Do you find that useful? Please share your experience.