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.
Most people with high blood pressure (known medically as hypertension) don't know they have it. Hypertension has no symptoms or warning signs. Yet it can be so dangerous to your health and well-being that it has earned the nickname "the silent killer." When high blood pressure is accompanied by high cholesterol and blood sugar levels, the damage to the arteries, kidneys, and heart accelerates exponentially.
High blood pressure is preventable. Daily exercise, following a healthy diet, limiting your intake of alcohol and salt, reducing stress, and not smoking are keys to keeping blood pressure under control. When it creeps into the unhealthy range, lifestyle changes and medications can bring it down.
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What Is It?
An abdominal aortic aneurysm is an abnormal swelling in the aorta. It can be fatal.
The aorta is the body's largest artery. It carries oxygen-rich blood from the heart to smaller arteries in the body.
An abdominal aneurysm occurs in the abdominal aorta. This is the part of the aorta between the bottom of the chest and the pelvis.
An abdominal aortic aneurysm usually causes a balloon-like swelling. The wall of the aorta bulges out.
Normally, the aorta is about one inch (2.5 centimeters) in diameter. The size increases very gradually as people age. If the abdominal aorta becomes larger than 3 centimeters, this is called an abdominal aortic aneurysm.
Most aortic aneurysms are related to atherosclerosis. In atherosclerosis, fatty deposits build up along the inside walls of blood vessels.
Tachycardia is a heart rate of more than 100 beats per minute. The heart normally beats at a rate of 60 to 100 times per minute, and the pulse (felt at the wrist, neck or elsewhere) matches the contractions of the heart's ventricles, the heart's two powerful lower chambers.
Atherosclerosis is a narrowing of the arteries that can significantly reduce the blood supply to vital organs such as the heart, brain and intestines. In atherosclerosis, the arteries are narrowed when fatty deposits called plaques build up inside. Plaques typically contain cholesterol from low-density lipoproteins (LDL), smooth-muscle cells and fibrous tissue, and sometimes calcium.
As a plaque grows along the lining of an artery, it produces a rough area in the artery's normally smooth surface. This rough area can cause a blood clot to form inside the artery, which can totally block blood flow. As a result, the organ supplied by the blocked artery starves for blood and oxygen. The organ's cells may either die or suffer severe damage.
Coronary artery disease (CAD) is the narrowing of coronary arteries. These are the blood vessels that supply blood and oxygen to the heart. The condition is also called coronary heart disease (CHD).
CAD is usually caused by atherosclerosis. Atherosclerosis is the buildup of plaque inside the coronary arteries. These plaques are made up of fatty deposits and fibrous tissue.
In most cases of high blood pressure (hypertension), there is no known cause. About 6% of the time, however, high blood pressure is caused by another condition or disease. When this happens, it is called secondary hypertension.
Most of the conditions that cause secondary hypertension involve the overproduction of one of the body's hormones. Some of the medical problems that can cause secondary hypertension include:
Kidney disease. Secondary hypertension can be related to damaged kidneys or to an abnormal narrowing of one or both renal arteries. The renal arteries are the major blood vessels that bring blood to each kidney. When the kidney's blood supply is reduced by a narrowing (called renal artery stenosis), the kidney produces high levels of a hormone called renin. High levels of renin trigger the production of other substances in the body that raise blood pressure, particularly a molecule called angiotensin II.
Adrenal disease. The adrenal glands sit on top of the kidneys and produce several hormones that help regulate blood pressure. Sometimes, one or both adrenal glands make and secrete an excess of one of these hormones.
Excess body fat has serious consequences for health. It' associated with high levels of LDL ("bad") cholesterol and triglycerides and low levels of HDL ("good") cholesterol. It impairs the body's responsiveness to insulin, raising blood sugar and insulin levels. Excess body fat contributes to major causes of death and disability, including heart attacks, strokes, high blood pressure, cancer, diabetes, osteoarthritis, fatty liver, and depression.
Faced with these risks, it's no wonder that you want to know how much you should weigh. But this common and important question is actually the wrong question. For health, the issue is not how much you weigh, but how much abdominal fat you have.
Methods have changed over the years. But when scientists recognized that what matters is not body weight but body fat, standards began to change. The body mass index (BMI), remains enshrined as the standard way to diagnose overweight and obesity.
At least half of the 80 million Americans with high blood pressure don't have it under control. Sometimes poor control stems from lack of trying. A growing number of people, though, have what's called resistant hypertension — blood pressure that stays stubbornly above the target (see "Blood pressure goals") in spite of lifestyle changes and medications.
Persistently high blood pressure is a problem. It is a key contributor to stroke, heart failure, and other cardiovascular conditions.
Strictly speaking, you have resistant hypertension if your blood pressure is still high even though you are taking three or more pressure-lowering medications, or if you need to take four or more medications to reach your blood pressure target.
When it comes to fighting high blood pressure, the average American diet delivers too much sodium and too little potassium. Eating to reverse this imbalance could prevent or control high blood pressure and translate into fewer heart attacks, strokes, and deaths from heart disease.
Normal body levels of potassium are important for muscle function. Potassium relaxes the walls of the blood vessels, lowering blood pressure and protecting against muscle cramping. A number of studies have shown an association between low potassium intake and increased blood pressure and higher risk of stroke. On the flip side, people who already have high blood pressure can significantly lower their systolic (top number) blood pressure by increasing their potassium intake when they choose to eat healthy foods.
Most Americans get barely half of the recommended amount of potassium — 4,700 milligrams (mg) a day. Fruits, vegetables, beans, and some seeds offer good ways to get more of it. Bananas (about 425 mg of potassium in a medium-sized one) are often held up as the poster child for potassium, but there are better sources.
Thiazide diuretics like hydrochlorothiazide (Esidrix, HydroDIURIL, other brands) continue to be a very effective way to lower blood pressure for people with hypertension. They're inexpensive, and results from large studies have shown them to be at least as effective as other types of blood pressure drugs for most patients.
But if you're taking a diuretic, your potassium levels need to be watched. These drugs direct the kidneys to pump water and sodium into the urine. Unfortunately, potassium also slips through the open floodgates. A low potassium level can cause muscle weakness, cramping, or an abnormal heartbeat, which is especially dangerous for people with heart problems.
Potassium pills are one solution, but some tend to taste bad, so people may neglect to take them. Eating foods rich in potassium, like bananas, may help, but often that's not enough. Spironolactone (Aldactone) and triamterene (Dyrenium) are diuretics that "spare" potassium, leaving levels high, but they're pretty weak as diuretics. Dyazide (available as a generic) is an attempt to strike a balance: It's part thiazide, part potassium-sparing diuretic.
This spring the National Institutes of Health revised the guidelines for prevention and treatment of high blood pressure (hypertension) for the first time since 1997. The changes included a new definition of "normal" blood pressure. This meant that 45 million Americans who had gone to sleep with normal blood pressure woke up with higher-than-healthy blood pressure. Here are some of the highlights:
It's a little strange. All of a sudden, the experts are telling millions of people who thought they were healthy that they now have this condition called prehypertension. But the idea is to get Americans and their doctors to take action before the blood pressure climbs any higher - and into the range where the risks of heart disease, stroke, and other problems are pronounced.
In the prehypertensive range, taking action does not mean taking pills. It means, for example, regular aerobic activity, such as 30 minutes of brisk walking several days per week. That kind of exercise can lower your blood pressure by 4-9 mm Hg. If you're overweight, losing about 22 pounds is "worth" a 5-20 mm Hg subtraction in systolic pressure. Limit your sodium intake to 2.4 grams daily and the benefit is a 2-8 mm Hg reduction.