Definition of High Blood Pressure

by Dr. Gabe Mirkin, M.D.

Ninety-one percent of North Americans will develop high blood pressure that puts them at increased risk for heart attacks, strokes, kidney disease, and diabetes and premature death. Lowering high blood pressure helps to prevent disease and prolong life. Blood pressure has two numbers: systolic, when the heart contracts, and diastolic, when it relaxes. The heart contraction (systolic) is most important. If your SYSTOLIC blood pressure is greater than 120, you have high blood pressure and should change your lifestyle to lower it. If it is greater than 140, your doctor usually prescribes pills in addition to lifestyle changes.

WHEN TO TAKE YOUR BLOOD PRESSURE

Take your blood pressure just before you go to bed at night. Blood pressure is usually lower then and just after you wake in the morning. Blood pressures that do not drop at bedtime or are high when you wake in the morning increase risk for heart attacks and strokes.

SALT

For most people, excess salt intake is associated with high blood pressure and a modest reduction in salt intake for four or more weeks will help lower it somewhat (Cochrane Database Syst Rev. March, 2004;3). However, many people do not develop high blood pressure when they take in large amounts of salt, and most people who have high blood pressure will not have a lowering of blood pressure when they try to restrict salt.

People are classified as salt sensitive and salt insensitive on the basis of whether their blood pressure rises with excess salt intake, but there is no readily available lab test to diagnose those who are salt sensitive. People who are overweight, diabetic or do not exercise are the ones most likely to develop high blood pressure from excess salt intake. These people should restrict salt. Exercisers sweat heavily and usually need to take in a lot of salt to replace their losses.

FACTORS ASSOCIATED WITH HIGH BLOOD PRESSURE

High blood pressure is associated with higher salt, alcohol or protein intake, and lower potassium, calcium or magnesium intake (Clin Care. Jan, 2002;5(1):9-19). Other risk factors for hypertension include obesity and lack of regular physical activity (European Heart Journal, Dec. 2011;32(24):3081-7).

• ALCOHOL: Women who take one alcoholic drink a day and men who take two are at decreased risk for high blood pressures. Taking more than that, or binging even occasionally, raises blood pressure.
• OVERWEIGHT: The fatter you are, the higher the blood pressure.
• LACK OF EXERCISE: Exercise often lowers high blood pressure.
• NOT EATING LOTS OF FRUITS AND VEGETABLES: A diet rich in fruits and vegetables and low in saturated and total fat (DASH diet) lowers high blood pressure.
• EATING TOO MUCH MEAT. A high-protein diet increases risk of high blood pressure.

Neither caffeine nor nicotine has been shown to cause sustained high blood pressure.

LIFESTYLE CHANGES TO LOWER HIGH BLOOD PRESSURE

• Lose weight if overweight
• Exercise regularly
• Eat a diet with plenty of fruits, vegetables, whole grains, beans, nuts and other seeds, and low in saturated fat (red meat) and refined carbohydrates. Avoid sugared drinks and if overweight, reduce your intake of foods made from flour or with added sugars.
• If you drink alcohol, limit yourself to one drink a day. (A drink is 12 ounces of beer, 5 ounces of wine, and 2/3rds of shot glass of alcohol)
• Check your blood pressure just before you go to bed at night