High Blood Pressure – Understanding the ‘Silent Killer’

Imagine going through your day feeling perfectly healthy, unaware that something could be silently affecting your well-being. High blood pressure, often called the “silent killer,” doesn’t always show obvious signs, but it can quietly increase your risk for serious health conditions. Many people live with high blood pressure without even realizing it, making it easy to overlook until it causes lasting harm.

The trouble with high blood pressure is that it doesn’t always come with clear symptoms. It slowly places more strain on your heart and blood vessels, gradually affecting your health in ways you might not notice right away.

We all have “blood pressure.” This refers to the way blood pushes against the walls of your arteries as your heart pumps.

However, nearly half of adults in the United States have high blood pressure, also known as hypertension.

What is high blood pressure?

High blood pressure occurs when the force exerted by circulating blood on the walls of blood vessels consistently remains elevated. This condition forces the heart to work harder than normal to pump blood through the body, which over time can lead to severe health complications like heart attack and stroke.

Your blood pressure is recorded as two numbers:

• Systolic blood pressure is the first (top/upper) number. It measures the pressure your blood is pushing against your artery walls when the heart beats.
• Diastolic blood pressure is the second (bottom/lower) number. It measures the pressure your blood is pushing against your artery walls while the heart muscle rests between beats.

Blood pressure is measured in millimeters of mercury (mm Hg) and is written as two numbers separated by a slash like this: 120/80 mm Hg.

Your blood pressure changes throughout the day based on your activities. It is lower during sleep and higher with physical exertion. A healthy systolic blood pressure is less than 120 mm Hg. A healthy diastolic pressure is less than 80 mm Hg. Your blood pressure is high when you have consistent systolic readings of 130 mm Hg or higher, or diastolic readings of 80 mm Hg or higher.

Measuring your blood pressure is the only way to find out if you have high blood pressure. An average based on two or more readings taken on two or more occasions by a health care professional is recommended for a proper diagnosis.

According to the National Institutes of Health, blood pressure is categorized as follows:

Consequences of high blood pressure

Unchecked high blood pressure can have a cascading effect on various organs and bodily functions. The increased force within blood vessels can damage the delicate lining of artery walls, causing tiny tears where plaque, consisting of cholesterol, fats, and other substances, can accumulate. This process, called atherosclerosis, leads to narrowing of the arteries and restricts blood flow. As arteries narrow, the heart must work even harder to circulate blood, which can result in a dangerous cycle of elevated blood pressure and further artery damage. Over time, this can increase the risk of:

• Dementia. High BP can damage blood vessels in the brain, increasing the risk of dementia and problems with memory, focus and other thinking skills.
• Stroke. High BP can cause blood vessels in the brain to burst or clog more easily.
• Vision Loss. High BP can damage the vessels in the eyes.
• Heart Failure. High BP can cause the heart to stiffen or enlarge, making it harder to pump blood effectively to the body.
• Heart Attack. High HP can damage arteries and cause them to narrow and stiffen.
• Kidney Disease/Failure. High BP can damage the arteries in the kidneys and interfere with their ability to effectively filter blood.
• Sexual Dysfunction. High BP can lead to erectile dysfunction in men and reduced sexual arousal in women.

Causes and risk factors for high blood pressure

Many factors raise your risk of getting high blood pressure. You can change some of the risk factors, such as unhealthy lifestyle habits. Other risk factors, such as age, family history and genetics, race, and sex, cannot be changed. But you can still take steps to reduce your risk of high blood pressure and its complications.

Common inherited and physical risk factors for high blood pressure include:

• Age: As you get older, you are more likely to get high blood pressure. Blood vessels naturally thicken and stiffen over time. These changes increase the risk of high blood pressure.
• Family history: High blood pressure often runs in families. If your parents or other close blood relatives have high blood pressure, you have an increased chance of getting it, too.
• Race or ethnicity: High blood pressure is more common in Black adults than in White, Hispanic, or Asian adults. Compared with other racial or ethnic groups, Black adults tend to have higher blood pressure and get high blood pressure earlier in life.
• Gender: Men are more likely than women to develop high blood pressure.
• Chronic kidney disease: High blood pressure may be caused by kidney disease. Having high blood pressure also may cause kidney damage.

Modifiable risk factors to help prevent and manage high blood pressure

1) Being overweight or obese. Blood pressure often increases as weight increases. Carrying extra weight can put more stress on the heart and blood vessels. Your heart must work extra hard to pump blood through the body. The harder your heart pumps, the higher your blood pressure.

Weight loss is one of the best ways to control blood pressure. If you’re overweight or have obesity, losing even a small amount of weight can help lower blood pressure. In general, blood pressure might go down by about 1 mm Hg with each kilogram (about 2.2 pounds) of weight lost.

The body mass index (BMI) uses height and weight to find out whether a person is overweight or obese. A BMI of 25 or higher is considered overweight.

BMI doesn’t take into account your muscle mass, bone density, or body composition. Even if two people have the same BMI, their amount of excess body fat may differ.

To find out if your weight is in a healthy range, calculate your BMI here. 

2) An unhealthy diet, especially one high in sodium. What you eat affects your blood pressure.  Eating a diet rich in whole grains, fruits, vegetables and low-fat dairy products, and low in saturated fat and cholesterol can lower high blood pressure by up to 11 mm Hg. The Dietary Approaches to Stop Hypertension (DASH) diet is an example of an eating plan that can help lower blood pressure.

Having less sodium in your diet may help you avoid or lower high blood pressure. When there’s extra sodium in your bloodstream, it pulls water into your blood vessels. This increases the amount of blood flowing through your blood vessels, which increases blood pressure. Over time, this may raise blood pressure or lead to high blood pressure in some people.

Most people in the U.S. consume too much sodium. The average person in the U.S. eats about 3,400 milligrams (mg) of sodium a day. The U.S. Food & Drug Administration recommends no more than 2,300 mg of sodium a day. This roughly equates to one teaspoon.

The best way to reduce sodium is to avoid processed and packaged foods and foods prepared at restaurants. They tend to be higher in sodium. Some common foods that add the most salt to your diet include:

• Pizza
• Bread, rolls and buns
• Sandwiches and burgers
• Burritos and tacos
• Rice, pasta and grain dishes
• Meat, poultry and seafood dishes
• Frozen dinners and snack foods
• Sauces, such as barbecue, soy and steak
• Soups

For most adults, it’s ideal to limit sodium to 1,500 mg a day or less. Doing that may lower high blood pressure by about 5 to 6 mm Hg.

For more information on healthy diet and nutrition, visit odphp.health.gov.

3) Low potassium levels. Potassium in the diet can lessen the effects of table salt and sodium on blood pressure. The more potassium you eat, the more sodium you lose through urine. Potassium relaxes the walls of the blood vessels, lowering blood pressure and protecting against muscle cramping. Increase potassium by aiming for 3,500-5,000 mg per day with foods like yams, spinach or bananas unless you have kidney problems or take certain medications. It may lower blood pressure by 4 to 6 mm Hg. Ask your healthcare professional how much potassium you should have.

For more information on food sources of potassium, visit dietaryguidelines.gov.

4) Lack of physical activity. Exercise helps reduce blood pressure by improving the function of the blood vessels and heart. Regular physical activity strengthens the heart, allowing it to pump blood more efficiently. Over time, exercise also improves the elasticity of the arteries, which helps them to expand and contract more easily. This means the heart doesn’t have to work as hard to pump blood, which can lower overall blood pressure.  

It takes about 1 to 3 months for regular exercise to have an impact on blood pressure. The benefits last only as long as you continue to exercise.

The U.S. Department of Health and Human Services’ Physical Activity Guidelines for Americans recommends that adults get at least 150 minutes per week of moderate-intensity aerobic activity or 75 minutes per week of vigorous aerobic activity (or a combination of both), preferably spread throughout the week. Also, include muscle-strengthening activity (like bodyweight resistance or weight training) at least twice a week.

Regular aerobic exercise can lower blood pressure by about 5 to 8 mm Hg.

For more information on physical activity, visit health.gov.

5) Sleep issues. Sleeping less than seven hours a night raises the risk of high blood pressure. Lack of ample sleep throws off your body’s circadian rhythm (internal clock), triggering a surge in stress hormones that cause blood vessels to narrow and blood pressure to rise.

Sleep deprivation is a modifiable risk that may be fixed with improved sleep hygiene. Sleep hygiene describes healthy habits, practices, and environmental factors that promote high-quality sleep.

For healthy sleep habits, visit NIH.gov.

6)Tobacco use or vaping. Smoking, chewing tobacco or vaping immediately raises blood pressure for a short time. Tobacco smoking injuries blood vessel walls and speeds up the process of hardening of the arteries.

If you smoke cigarettes, you can find resources to help you on your journey to a smoke-free life at Smokefree.gov.

7) Drinking too much alcohol. Drinking too much alcohol can raise pressure on the walls of blood vessels to unhealthy levels.

The effect is more pronounced with binge drinking, which places sudden stress on the cardiovascular system and can cause significant fluctuations in blood pressure. Over time, repeated episodes of elevated blood pressure from alcohol use can contribute to long-term hypertension and increase the risk of serious heart problems.

Limiting alcohol to less than one drink a day for women or two drinks a day for men can help lower blood pressure by about 4 mm Hg. One drink equals 12 fluid ounces of beer, 5 ounces of wine or 1.5 ounces of 80-proof liquor.

For more information on preventing alcohol misuse, visit NIH.gov.

Comprehensive information on how to prevent high blood pressure can be found at the Centers for Disease Control and Prevention website at cdc.gov.