Blood pressureis a measurement of the force of your blood pushing against your artery walls when it travels from your heart to the rest of your body. Blood pressure below 120/80 is normal. Blood pressure is generally considered low when it’s less than 90/60.

High blood pressure, calledhypertension, increases the risk ofheart attack和stroke。Low blood pressure, calledhypotension, increases the risk of:

If you check your blood pressure at home, a number of factors can affect your blood pressure readings. Read on to learn how eating, not eating, diet, and other factors can affect these readings.

If your doctor has suggested measuring your blood pressure at home, it’s likely they’ve recommended you take your morning measurement before eating. That’s because the reading will often be lower than is typical following a meal.

When you eat, your body directs extra blood to the stomach and small intestine. At the same time, blood vessels that are distant from your digestive system narrow, and your heart beats harder and faster.

此动作将血液流量和血压维持到您的大脑，四肢和身体的其他地方。

If your blood vessels and heart don’t respond correctly to the extra blood directed to your digestive system, blood pressure everywhere but the digestive system will decrease. This is calledpostprandial hypotension。

Postprandial hypotension can result in:

According to a 2010 research review , postprandial hypotension may affect up to 33 percent of older adults living in nursing homes.

Fasting can help lower blood pressure. It can also result in anelectrolyte imbalance。这可以让心脏容易发生arrhythmias, or problems with the rhythm or rate of your heartbeat.

Discuss fasting with your doctor before trying it.

You can affect your blood pressure with diet.

If you have high blood pressure, you can lower it by altering what you eat. The膳食方法阻止高血压（破折号）饮食can lower your blood pressure up to 11 mm Hg 。

The DASH diet is low in saturated fat and cholesterol and rich in:

  • vegetables
  • fruits
  • 低脂肪乳制品
  • 全谷类

It is important to note the DASH diet also includes limiting salt and added sugars.

Reducing sodium can also lower blood pressure

Reducing sodium in your diet, even by a small amount, can reduce your blood pressure.

A 2015 study found theMediterranean dietcan lower blood pressure as well. It’s similar to the DASH diet, but higher in fat.

The fat in the Mediterranean diet is primarily monounsaturated fat from nuts, seeds, and olive oil. The study also suggested getting enough of the following may lower blood pressure:

  • potassium
  • magnesium
  • protein
  • fiber

If you’re monitoring your blood pressure at home, there are many factors that might affect the reading, including:

  • Exercise.Take your blood pressure before exercise or you might get an elevated reading.
  • Meals.In the morning, take your blood pressure before eating, as digesting food can lower your blood pressure. If you must eat first, wait 30 minutes after eating before taking a measurement.
  • Bathroom.A full bladder can give you an elevated reading. Empty it before taking a measurement.
  • Cuff size.If the monitor’s cuff doesn’t properly fit your upper arm, you may get inaccurate readings. Your doctor can tell you if your monitor’s cuff fits properly. If it doesn’t, they can show you how to position it for best results.
  • Clothing.准确的阅读，不要把袖口放在衣服上;把它放在裸露的皮肤上。如果你需要把袖子卷起到你的手臂上的重点，请脱掉衬衫或把你的手臂从袖子里拿出来。
  • Temperature.If you’re cold, you might get a higher than expected reading.
  • Position.For consistent and comparable results, always use the same arm and position it properly. It should be rested at the level of your heart on a chair arm or table. Your back should be supported and your legs should be uncrossed.
  • 压力。To get the most accurate reading, avoid stressful thoughts and sit in a comfortable position for 5 minutes before taking a measurement.
  • Talking.Avoid talking when taking your blood pressure, as it could elevate the measurement.

To make sure you’re getting accurate information, bring your home blood pressure monitor to your doctor’s office once a year. You can compare its readings with the readings from your doctor’s equipment.

Have your blood pressure checked as part of your regular doctor’s visits. When you’re ages 18 to 39, ask your doctor for a blood pressure reading every 3 to 5 years, if you are not at risk for high blood pressure and have a prior “normal” blood pressure reading.

If you have a high risk for high blood pressure, are overweight, or are over age 40, ask for a reading every year.

Call your doctor if you:

  • have a high blood pressure reading (above 120/80) and you haven’t received a diagnosis of hypertension
  • 有良好的血压，但它以上的“正常”范围超过一次
  • are concerned that your blood pressure medication is causing side effects

A number of factors can affect your blood pressure, including eating a meal. That typically lowers blood pressure.

If you have high blood pressure, a diet like the DASH or Mediterranean diet can help lower it.

It’s important for your doctor to monitor your blood pressure if your blood pressure is regularly too high or too low. Regularly high blood pressure increases the risk of heart attack and stroke and regularly low blood pressure increases the risk of heart and brain damage.

如果您的医生建议您在家里监控血压，则一些因素会影响读数，例如：

  • measuring too soon after eating a meal
  • exercising
  • consuming alcohol, tobacco, or caffeine
  • 有一个不适合或放在衣服上的袖口
  • 没有放松和坐在正确的位置

By working with your doctor, you can get your blood pressure to a measurement that’s healthy for you.