While there is no “normal” blood pressure reading, doctors now know enough about the relationship between blood pressure and heart disease and other diseases as well to know which range of blood pressure readings is safer and which is more dangerous.

Ideally, your doctor would like to see your blood pressure levels lower than 120 over 80 (120/80), though higher levels are still considered within a lower risk range. The most authoritative recommendations about blood pressure derive from the National Institutes of Health’s Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, which represents the opinion of the nation’s experts.

These guidelines recommend that everyone’s blood pressure should be lower than 140/90, because just above that level, known as Stage 1 hypertension, there is agreement that your risk is higher than it should be. As a result, the target blood pressure for most people is 140/90 or lower.

For every 20 mmHg increase in a person’s systolic blood pressure or every 10 mmHg increase in a person’s diastolic blood pressure, the risk for heart problems or stroke doubles. While the Joint National Committee urges most people to keep their blood pressure below 140/90, they set even lower targets for patients with a higher risk of health problems due to hypertension.

If you have diabetes or kidney failure (a condition where the kidneys are unable to filter the body’s blood as effectively as needed), the committee recommends that your blood pressure should be below 130/80. If you have heart disease, there’s a good chance you have high blood pressure as well; the two often go hand in hand.

Taking charge of your heart disease means taking charge of your hypertension, because reducing your high blood pressure can reduce your risk for more severe heart trouble by 20 percent. Many studies have shown that lowering high blood pressure also reduces your risk for stroke by at least 30 percent and your risk of dying from a heart problem or stroke by at least 20 percent.

If, as a result of several measurements, your blood pressure is consistently above the target levels, your doctor will probably recommend other tests, including urinalysis (urine test), a blood count, a blood chemistry analysis (testing levels of potassium, sodium, creatinine [an indicator for kidney disease], and glucose [blood sugar]), a check of your cholesterol levels, and perhaps an electrocardiogram.

Each of these tests tells the doctor something about your risk, the possible causes of your hypertension (including some rare causes that may require special treatment), their consequences, and your potential risk for further disease. Doctors often classify hypertension into two forms.

The first and most common type is known as essential hypertension. The cause is not known and is under active investigation, though it may be associated with narrowed and stiff arteries. The second, and more unusual, form is called secondary hypertension.

As its name suggests, in this case the hypertension is actually secondary to some other condition altogether, such as kidney disease, and is best addressed by treating that other underlying disease. Your doctor may suspect secondary hypertension if your blood pressure fluctuates significantly, is extremely high, doesn’t respond to hypertension medications, or has been present since you were young.

For most people, no other cause is ever found and they are left with a diagnosis of essential hypertension. Whatever its form, hypertension is dangerous and you may well want to keep track of your blood pressure more frequently than just when you see your doctor. There are many options for people who want to keep close watch on their blood pressure.

You may be able to have your blood pressure checked free at your local drugstore or supermarket. But you may also wish to purchase a blood pressure monitoring device you can use at home. If you do, you should know that home monitoring devices can vary in quality. So be sure to bring your device along when you visit your doctor to compare your readings with your doctor’s device on a regular basis.

Lowering Blood Pressure with Lifestyle Changes

The good news about high blood pressure is that it’s readily treatable and much of the treatment is within your own control. The expert recommendations for what you should do to treat your hypertension depend upon your blood pressure readings.

If you have heart disease and your blood pressure is in what’s called the “high-normal” range (systolic 130–139; diastolic 85–89), you may not require medication. Your doctor will probably recommend that you first try to reduce your blood pressure by changing your lifestyle.

It’s easy to dismiss this advice, but there is excellent evidence that this approach can make a big difference. In addition, if you can avoid medications, you can avoid their cost and potential adverse effects. Before going on medication, you should give a drug-free strategy a chance.

This “lifestyle approach” to treatment may involve five steps:

1. Lose your extra weight. Studies show that if you are overweight, losing even 10 pounds will lower your blood pressure. And if you do need to take blood pressure–lowering medications, cutting your weight will increase their effectiveness.

2. Limit your alcohol to no more than 24 ounces of beer, 20 ounces of wine, or 2 ounces of whiskey per day. Excess alcohol can not only cause hypertension and stroke, but can also interfere with blood pressure–lowering medications.

3. Exercise 30 to 45 minutes per day, most days of the week. People who are inactive have a 20 to 50 percent higher chance of developing hypertension. If you do have hypertension, moderate physical activity can lower your blood pressure.

4. Reduce your salt intake to no more than about 1 teaspoon of table salt (or 2.4 grams of sodium) per day. Many people are salt-sensitive when it comes to their blood pressure. Reducing the amount of salt you consume may gradually reduce both your blood pressure and, for those on drugs, the amount of blood pres-sure–lowering medication you need to take.

Even if you cannot get down to 1 teaspoon, lowering your salt intake by any amount can still make a difference. It’s not enough simply to use less salt from the salt shaker at the dinner table: 75 percent of the salt we ingest comes from processed food. Check the sodium content on the nutrition labels of everything you buy at the grocery store, and ask about salt content when ordering in restaurants.

5. Quit smoking. Blood pressure goes up when you smoke. Smoking may also prevent you from getting the full benefit of blood pressure–lowering medications.