High Blood Pressure (hypertension) Causes, Symptoms, Diagnosis, Treatment, and Prevention on MedicineNet.com

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High Blood Pressure
(Hypertension)

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Revising Medical Author: John P. Cunha, DO, FACOEP
Revising Medical Editor: Jay W. Marks, MD

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Low-Carb Diet Lowers Blood Pressure

Jan. 25 (WebMD Health News) -- A low-carbohydrate diet may have health benefits that go beyond weight loss.

A new study shows that a low-carbohydrate diet was equally good as the weight loss drug orlistat (the active ingredient in Alli and Xenical) at helping overweight and obese people lose weight, but people who followed the low-carb diet also experienced a healthy drop in their blood pressure levels.

"I expected the weight loss to be considerable with both therapies but we were surprised to see blood pressure improve so much more with the low-carbohydrate diet than with orlistat," researcher William S. Yancy, Jr., MD, an associate professor of medicine at Duke University Medical Center, says in a news release. "If people have high blood pressure and a weight problem, a low-carbohydrate diet might be a better option than a weight loss medication."

"Researchers say studies have already shown that ...

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What is high blood pressure?

High blood pressure (HBP) or hypertension means high pressure (tension) in the arteries. Arteries are vessels that carry blood from the pumping heart to all the tissues and organs of the body. High blood pressure does not mean excessive emotional tension, although emotional tension and stress can temporarily increase blood pressure. Normal blood pressure is below 120/80; blood pressure between 120/80 and 139/89 is called "pre-hypertension", and a blood pressure of 140/90 or above is considered high.

The top number, the systolic blood pressure, corresponds to the pressure in the arteries as the heart contracts and pumps blood forward into the arteries. The bottom number, the diastolic pressure, represents the pressure in the arteries as the heart relaxes after the contraction. The diastolic pressure reflects the lowest pressure to which the arteries are exposed.

An elevation of the systolic and/or diastolic blood pressure increases the risk of developing heart (cardiac) disease, kidney (renal) disease, hardening of the arteries (atherosclerosis or arteriosclerosis), eye damage, and stroke (brain damage). These complications of hypertension are often referred to as end-organ damage because damage to these organs is the end result of chronic (long duration) high blood pressure. For that reason, the diagnosis of high blood pressure is important so efforts can be made to normalize blood pressure and prevent complications.

It was previously thought that rises in diastolic blood pressure were a more important risk factor than systolic elevations, but it is now known that in people 50 years or older systolic hypertension represents a greater risk.

The American Heart Association estimates high blood pressure affects approximately one in three adults in the United States - 73 million people. High blood pressure is also estimated to affect about two million American teens and children, and the Journal of the American Medical Association reports that many are under-diagnosed. Hypertension is clearly a major public health problem.