If you’ve been diagnosed with high blood pressure, lowering it to a healthy level has been proven to reduce your risk of a litany of health problems, including heart attack, stroke, and kidney damage. Yet, of the 75 million Americans who have high blood pressure, only about half have it under control. That’s according to a recent report from the Centers for Disease Control and Prevention in collaboration with the Centers for Medicare & Medicaid Services.

“The fact is that high blood pressure is a leading cause of death in the U.S. and it is very poorly treated. Every year, more than 1.5 million Americans have a heart attack or stroke and high blood pressure is a key factor in those incidents,” says CDC director Tom Frieden, M.D.

Another concern: “One in six people with high blood pressure are not aware of it,” Frieden says.

That’s not surprising. High blood pressure is nicknamed “the silent killer” because levels can creep up without causing any symptoms at all. “Many patients have sky-high blood pressure and feel completely fine until the day they have a stroke or a heart attack,” Frieden says.

High blood pressure affects children, too. According to a study published this week in the Journal of Pediatrics, high blood pressure has increased significantly among children, paralleling the rise in obesity. The researchers found that compared to children with normal blood pressure, children with high blood pressure performed worse on cognitive tests, including memory and verbal skills.

The good news: At least in adults, controlling blood pressure can be done inexpensively and effectively. Here are four key factors in managing your blood pressure, plus links to Consumer Reports’ in-depth advice on treatment—and avoiding the problem to begin with.

Know Your Numbers

Ideally, you should have a systolic blood pressure of less than 120 millimeters of mercury (the top number) and a diastolic blood pressure (the bottom number) of less than 80 mmHg.

Have your blood pressure checked by a qualified health professional at least every two years, and at least annually if your readings are 120 over 80 or higher.

“Ask for the results, and don’t assume that your healthcare provider will flag worrying numbers,” says Marvin M. Lipman, M.D., Consumer Reports chief medical adviser. According to the CDC, most people with undiagnosed and uncontrolled hypertension have seen a healthcare provider at least twice in the past year. “If your numbers are higher than normal, be proactive and discuss your risk for high blood pressure with your doctor,” Lipman says.

Consider a Home Monitor

If you’ve had a higher-than-normal reading, a home blood-pressure monitor can help you track your numbers and monitor your health. And if your doctor has prescribed medication, it’s a good way to see if it’s working.

Sharing a log of your home test results can be especially helpful for patients who get nervous in the doctor’s office, causing their blood pressure to rise higher than usual, a phenomenon known as “white coat hypertension.”

Use our ratings to help you find a blood pressure monitor that’s best suited to your needs. At home or in the doctor’s office, these six tips—from uncrossing your legs to using the bathroom before the test—will help you get the most accurate readings.

Make Lifestyle Changes

Eating a heart-healthy diet, exercising, and losing weight are powerful tools in the fight against high blood pressure.

In some cases, committing to blood-pressure-friendly changes may even eliminate the need for medication. For example, cutting your daily salt intake to no more than 2,300 mg (the amount in a single teaspoon) can lower your systolic blood pressure by 2 to 8 mmHg. Taking a brisk 30-minute walk each day can bring that number down by 4 to 9 mmHg. This report provides detailed information about lifestyle changes that lower blood pressure. 

Take the Right Amount of the Right Medication

For high blood pressure, doctors commonly prescribe a group of drugs called thiazide diuretics, sometimes referred to as “water pills.” But depending on your individual needs, your doctor may prescribe a different type of medication.

To find out more about specific blood pressure drugs—including the cost, how effective they are, and their potential side effects—read our Consumer Reports Best Buy Drugs report. “But don’t let the threat of side effects deter you from taking the medication if it’s been prescribed,” Lipman says.