Controlling Your Blood Pressure

Blood pressure has gotten a bad rap. Some pressure is essential for circulation. Without it, blood couldn't move from the heart to the brain and the toes and back again. The heart provides the driving force — each contraction of the left ventricle, the heart's main pumping chamber, creates a wave of pressure that passes through all the arteries in the body. Relaxed and flexible arteries offer a healthy amount of resistance to each pulse of blood.

But too much of a good thing is a bad thing. Arteries that are tensed, constricted, or rigid offer more resistance. This shows up as higher blood pressure, and it makes the heart work harder. This extra work can weaken the heart muscle over time. It can damage other organs, like the kidneys and the eyes. And the relentless pounding of blood against the walls of arteries causes them to become hard and narrow, potentially setting the stage for a heart attack or stroke.


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What Is blood pressure?

Blood pressure has two components:

  • Systolic pressure is the top number. It represents the pressure the heart generates when it beats to pump blood to the rest of the body.
  • Diastolic pressure is the bottom number. It refers to the pressure in the blood vessels between heartbeats.

Blood pressure is measured in millimeters of mercury (mm Hg). So blood pressure would be expressed, for example, as 120/80 mm Hg.

High blood pressure is diagnosed when one or both of these numbers is too high. High blood pressure is also called hypertension.

For decades, high blood pressure was defined as 140/90 mm Hg. In November, 2017, new United States guidelines lowered the threshold for diagnosing the condition. According to new guidelines, anyone with a reading of 130/80 mm Hg or higher has high blood pressure. Normal blood pressure is less than 120/80 mm Hg. Based on this new definition, nearly half of Americans now fall into this group.

What is normal blood pressure? Blood pressure is now categorized as follows:

  • Normal blood pressure: Less than 120/80 mm Hg
  • Elevated blood pressure: 120/80 to 129/79 mm Hg
  • Stage 1 hypertension: 130/80 to 139/89 mm Hg
  • Stage 2 hypertension: 140/90 mm Hg and above

How do I know if my blood pressure is high?

Although high blood pressure can cause symptoms such as headache and pounding heartbeat, it often causes no symptoms at all.
So why worry about high blood pressure? Because even when high blood pressure is not causing any symptoms, it can silently damage many organs, including the:

  • Brain
  • Eyes
  • Heart
  • Kidneys
  • Arteries throughout the body

You may not recognize the damage that silent hypertension has been doing to your body until you suddenly are stricken with a major disease. For example, hypertension increases your risk of heart attack, stroke, and kidney failure.

Usually, hypertension does not directly cause symptoms. When blood pressure is very high, it can cause:

What’s the best way to check your blood pressure?

The diagnosis of hypertension depends on blood pressure readings. Therefore, it's essential that blood pressure be measured carefully.

Whether you take your blood pressure at home or in the doctor’s office, you want to get an accurate measurement. Here’s what you should do:

  • Avoid the following for at least one hour before you have your blood pressure taken:
    • Strenuous exercise
    • Smoking
    • Eating
    • Drinking caffeinated beverages
    • Be seated for at least five minutes before the reading is taken.
    • Do not talk while your blood pressure is being measured.
  • Two readings should be recorded and averaged.

If your blood pressure is high, your need an office visit so your doctor can examine your eyes, heart, and nervous system, to look for evidence of damage from hypertension.

If you are diagnosed with hypertension, other tests will check for organ damage. These tests can include:

  • Blood tests to check kidney function
  • An electrocardiogram (EKG) to look for:
    • Thickening of the heart muscle
    • Irregular heart rhythms
  • A chest x-ray to look for:
    • Enlargement of the heart
    • Fluid buildup in the lungs due to heart failure

Can high blood pressure be prevented?

To help prevent high blood pressure:

  • Get regular aerobic exercise
  • Limit your intake of salt and alcoholic beverages
  • Eat a diet rich in fruits and vegetables and low in saturated fats
  • Avoid smoking
  • Maintain a desirable body weight

Hypertension increases your risk of heart attack and stroke. So it is important to also pay attention to other risk factors, such as high LDL (bad) cholesterol.

You may be able to cure your hypertension with lifestyle changes alone. Simply changing what you eat and drink can bring down systolic blood pressure by as much as 11 points, according to some estimates.

Who needs treatment to lower blood pressure?

Elevated blood pressure. If your blood pressure is simply elevated, meaning the first number (systolic blood pressure) falls in the range of 120 to 129 while the second number (diastolic blood pressure) remains below 80, medication is not recommended.
Instead, you should focus on healthy lifestyle changes:

Stage 1 hypertension. You have stage 1 hypertension if your systolic blood pressure is 130 to 139, your diastolic pressure is 80 to 89, or both. Even if your systolic blood pressure hovers above 130, you still may not need medication immediately. Your doctor may suggest a trial of lifestyle changes first if you don't have heart disease and you have a low risk of developing it over the next 10 years. But many people find that they need to take some type of medication in order to reduce their blood pressure numbers to healthier levels.

Stage 2 hypertension. You have stage 2 hypertension if your systolic pressure is at least 140 mm Hg, your diastolic pressure is at least 90 mm Hg, or both. In addition to lifestyle modifications, you will likely need to start medication to lower your blood pressure. That doesn't mean you will always need drug therapy. Losing weight, decreasing stress, eating healthier, and exercising daily can potentially bring your readings into the normal range. But even if you still need medication, your lifestyle efforts help prevent you from needing higher drug doses in the future.

Examples of commonly used antihypertensive medications include:

  • Diuretics
  • ACE inhibitors
  • Angiotensin-receptor blockers (ARBs)
  • Calcium channel blockers

People with diabetes, kidney disease or heart problems are at higher risk of complications from hypertension. As a result, they are usually treated more aggressively with medications.

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