What is blood pressure?
Blood pressure is the force of blood against the walls of the blood vessels. A blood pressure reading has two numbers separated by a slash—the systolic pressure and diastolic pressure:
- The systolic pressure (the top or first number) is the force of blood in the arteries when your heart contracts.
- The diastolic blood pressure (the bottom or second number) is the force of blood in the arteries when your heart relaxes.
How can high blood pressure affect the blood vessels?
Long-term high blood pressure can damage blood vessels. The buildup of plaque also can lead to a narrowing of blood vessels. Plaque is a fatty substance that forms in the arteries when too much cholesterol is present (see the FAQ Cholesterol and Women's Health). Over time, plaque causes the arteries to narrow and harden. This condition is called atherosclerosis. The combination of atherosclerosis and high blood pressure sets the stage for stroke and heart attack.
How does high blood pressure affect the heart?
As blood pressure increases, the heart has to work harder to deliver oxygen to the tissues. Over time, the heart enlarges and may have trouble doing its work. This can lead to heart failure.
How does high blood affect the brain?
High blood pressure can cause a blood vessel in the brain to burst and lead to stroke. Brain cells in that part of the brain may die. A stroke that continues for a few minutes can cause permanent brain damage or death. Depending on the part of the brain affected, signals from the brain to the body can be disrupted and affect speech, movement, and other body functions.
How does high blood pressure affect the kidneys?
The kidneys filter the blood to remove waste from your body. The blood vessels in the kidneys can be easily damaged by high blood pressure. When the kidneys are not working normally, their ability to control salt and water balance in the body is disrupted. This can lead to kidney failure.
How can high blood pressure affect the eyes?
High blood pressure can also narrow the blood vessels in the eyes. This can cause your vision to become worse and may even lead to blindness.
What factors increase the risk of high blood pressure?
Lifestyle habits can increase your risk of high blood pressure. Women who are overweight, are not physically active, smoke cigarettes, or drink large amounts of alcohol are more at risk. Diet and stress also play a role. Other factors that increase the risk of high blood pressure that are not related to lifestyle habits include the following:
- Age — Blood pressure goes up with age, and high blood pressure occurs most often among women older than 40 years.
- Race — High blood pressure is more common in African Americans than in any other racial group.
- Family history — High blood pressure tends to run in families.
- Medical conditions — Certain diseases, such as diabetes and kidney disease, can be linked to high blood pressure.
How can I reduce the risk of high blood pressure?
You can reduce your risk of high blood pressure and its long-term effects by adopting a healthy lifestyle. The following methods may help lower your blood pressure:
- Lose weight (see the FAQ Weight Control: Eating Right and Keeping Fit)
- Exercise regularly (see the FAQ Exercise and Fitness)
- Quit smoking (see the FAQ It’s Time to Quit Smoking)
- Limit alcohol drinking — Heavy alcohol drinking (more than two drinks a day) is linked to an increase in blood pressure.
- Cut back on salt — Heavy salt (sodium) consumption can increase blood pressure in some people.
- Change your diet —The DASH eating plan (Dietary Approaches to Stop Hypertension) focuses on heart-healthy foods that are low in fat and cholesterol (see the FAQ Healthy Eating).
- Relieve stress
How is high blood pressure treated?
Your health care provider may prescribe medications to lower your high blood pressure. He or she will discuss with you which ones are best for your condition.
Medications to treat high blood pressure can have side effects. If you think you are having any side effects, talk to your health care provider. It is possible that you can try a different therapy. Do not stop taking your medication, which can cause your blood pressure to increase to a very high level. It is important to continue taking your medication even when you are feeling healthy.
Atherosclerosis: Narrowing and clogging of the arteries by a buildup of plaque deposited in vessel walls; also called "hardening of the arteries."
Cholesterol: A fat-like substance found in animal fats and oils.