For many people, as they age, their blood pressure will rise. Your blood pressure is optimal, the National Heart, Lung and Blood Institute (NHLBI) says, when your systolic blood pressure (the top number) is below 120, and when your diastolic blood pressure (the bottom number) is below 80. Blood pressure in which either the top number is 120-139 or the bottom number is 80-89 on three or more occasions is considered prehypertension. Prehypertension means you are at an increased risk to develop hypertension in the future.
High blood pressure, or hypertension, is when the top number is 140 or higher and the bottom number is 90 or higher on three or more occasions. Hypertension increases your risk for heart disease, kidney disease and stroke.
The NHLBI estimates that about 65 million American adults--nearly 1 in 3--have high blood pressure and middle-aged Americans face a 90% chance of developing high blood pressure during their lives. Among African Americans, hpertension is more common. The American Heart Association estimates that more than 40 percent of African Americans have high blood pressure. African Americans develop high blood pressure at a younger age, and have a higher death rate from stroke and kidney disease than whites.
You can take steps to prevent high blood pressure by adopting a healthy lifestyle that includes:
Maintaining a healthy weight;
Being physically active;
Following a healthy eating plan, that emphasizes fruits, vegetables, and low fat dairy foods;
Choosing and preparing foods with less salt and sodium;
If you drink alcoholic beverages, drink in moderation.
The DASH diet -- short for Dietary Approaches to Stop Hypertension is a diet that has been shown to reduce elevated blood pressures. It is an eating plan that emphasizes fruits, vegetables, and low fat dairy foods and is low in saturated fat, total fat, and cholesterol.
Studies that developed the DASH diet included people with "higher than optimal" blood pressure. In a study reported in 1997, the DASH diet caused average blood pressure readings to fall as much as they would have with a blood pressure drug.
In that study, the DASH diet used about 3,000 milligrams of sodium daily. "DASH-Sodium," a second study, found in 2001 that cutting salt within the DASH diet helps blood pressure even more. The DASH diet currently recommends 2400 mg of sodium, or less, each day. The newly released (2005) Dietary Guidelines for Americans calls for consuming less than 2300 mg of sodium a day. Either recommendation means you should limit yourself to about a teaspoon of table salt a day. Limiting daily sodium to 1,500 mg helps lower blood pressure even more.
Only about 15 percent of sodium comes from the saltshaker. Ten percent occurs naturally in food and 75 percent comes from food processing. Read labels and choose products that say "no salt" and "low salt." Food preparation also can add sodium. Baked items prepared with baking powder or baking soda have a high sodium content.
The DASH diet is rich in potassium, magnesium and calcium, as well as protein and fiber, and low in sodium. It calls for eight to ten servings of fruits and vegetables. It emphasizes whole grains and consistent use of low-fat dairy products. The big "no" is sweets, limited to small amounts five times a week.
"You can cut back gradually on high-fat and salted foods while you add fruit or vegetables to your meals," Dr. Obarzanek says.
The number of servings is based on 2,000 calories a day and, depending on your choices, will contain either 2,400 mg or 1,500 mg of sodium a day. Each food listed makes up one serving.
7-8 daily servings of grains and grain products: 1 slice bread, 1 ounce dry cereal, 1/2 cup cooked rice, pasta or cereal (G)
4-5 daily servings of vegetables: 1 cup raw leafy vegetable, 1/2 cup cooked vegetable, 6 ounces vegetable juice (V)
4-5 daily servings of fruit: 6 ounces fruit juice, 1 medium fruit, 1/4 cup dried fruit, 1/2 cup fresh, frozen or canned fruit without added sugar (F)