More than 65 million Americans - or one in three adults - have high blood pressure, or hypertension. High blood pressure is called "the silent killer" because there are no signs or symptoms of it. Most people do not know they have high blood pressure unless a doctor tells them.

Blood pressure is defined as the force of blood against artery walls. When this pressure is high, the heart has to work harder to pump blood throughout the body. This high force of blood flow, if left untreated, can cause damage to your arteries, heart, kidneys, eyes, and other organs.

High blood pressure can be controlled by maintaining a healthy weight, being physically active, only drinking alcohol in moderation, not smoking, taking prescribed blood pressure medication, and eating a healthy diet. Most people have heard that if you have high blood pressure, you should limit your intake of salt. However, there are many dietary changes, in addition to decreasing salt intake, to help lower blood pressure:

• Salt/Sodium: Limit salt and foods containing excess sodium, such as canned and frozen foods, soups, cured and smoked meats, and snack mixes and chips. Look for low-sodium versions of your favorite foods.
  
  Increased sodium intake causes excess fluid to be retained in the blood vessels. This increases blood volume and requires the heart to work harder to pump blood to all the tissues in the body. Increasing the blood's volume in the circulatory system is one way that salt increases blood pressure.

• Magnesium: Increase foods rich in magnesium. The best sources of magnesium are black beans, broccoli, spinach, pumpkin seeds, sunflower seeds, and peanuts/peanut butter.
  
  Magnesium is needed for more than 300 biochemical reactions in the body. It helps promote normal blood pressure by relaxing nerves and muscles and maintaining normal blood circulation.

• Calcium: Increase foods rich in calcium, such as low-fat dairy products, eggs, green leafy vegetables, broccoli, legumes, nuts, and whole grains.
  
  Calcium plays several important roles in controlling blood pressure, such as conducting nerve impulses, contracting muscles, secreting hormones, aiding blood clotting, and activating certain enzymes.

• Potassium: Increase foods rich in potassium. The best sources of potassium are potatoes, sweet potatoes, tomatoes, bananas, oranges, orange juice, yogurt, apricots, zucchini, beans, almonds, and pork.
  
  One way in which potassium helps control blood pressure is by making blood vessels less sensitive to compounds, like hormones, that normally cause blood vessel contraction. Less contraction leads to lower overall blood pressure.

Reducing sodium intake and increasing your intake of foods rich in magnesium, calcium, and potassium can have a large impact on your blood pressure and your overall health. Studies have shown that these key nutrients work synergistically to help lower blood pressure, so it is important to eat a variety of the healthy foods listed above each day. Remember, while dietary changes can play a crucial role in reducing and controlling blood pressure, they are not a substitute for medical care. Make sure to have your blood pressure checked routinely by a medical professional.

Resources:

Windhauser, M., Ernst, D., Karanja, N., Crawford, S., Redican, S., Swain, J., Karimbakas, J., Champagne, C., Hoben. K., Evans, M. (1999). Translating the dietary approaches to stop hypertension from research to practice: Dietary and behavior change techniques. Journal of the American Dietetic Association, 99(8), S90-S95.

The Dash Diet
http://www.nhlbi.nih.gov/hbp/prevent/h_eating/h_eating.htm

The American Heart Association
http://www.americanheart.org