High blood pressure affects one out of every three adults. About 70 million people in the United States have high blood pressure, but only half have their blood pressure under control. High blood pressure has been called the silent killer, because it rarely causes symptoms. The only way to reliably tell if you have high blood pressure is to measure it with a blood pressure machine.

Blood pressure is measured in millimeters of mercury even though blood pressure machines that use mercury have nearly all been replaced. A blood pressure of less than 120/80 is considered normal. The highest number is called the systolic blood pressure. The lower number is called the diastolic blood pressure.

Complications from high blood pressure increase with every millimeter of blood pressure elevation. At a blood pressure of 140/90 the risk has increased so high that treatment should be started. If your blood pressure is between 120/80 and 139/89 you should work on lifestyle changes to prevent high blood pressure. For every 20 millimeter increase in systolic blood pressure the risk of heart disease doubles.

The three main complications from high blood pressure are stroke, heart attack and heart failure.   Treatment reduces complications by approximately one-third for stroke, one-quarter for heart attacks and half for heart failure. Other benefits include reduction in kidney and eye disease.

Exercise is a key lifestyle change. A common recommendation is to exercise at least five times a week with a regimen such as brisk walking for 30 minutes. Diet can also lower blood pressure, especially diet with weight loss. Lowering the amount of salt in the diet is very helpful. Ideally eat no more than 1500 mg of salt. Unfortunately, most processed foods have added salt. To limit salt to 1500 mg or less, most people need to eat primarily fresh food.

A diet recommended for lowering blood pressure is the DASH diet. In addition to lowering sodium, the DASH diet focuses on eating foods that are high in potassium, calcium, magnesium, fiber and protein. The diet includes eating four to five vegetable servings, four to five fruit servings and six to eight grain servings per day for 2,000 calories per day. The DASH diet is also low in saturated and trans fats by allowing no more than six meat servings per day with an emphasis on fish and poultry. Further information is found at https://www.nhlbi.nih.gov/health/health-topics/topics/dash.

Other helpful lifestyle changes include limiting alcohol to no more than two drinks per day and not smoking. If lifestyle changes do not lower blood pressure, medication is advised next. There are many types of blood pressure medications available today, and it is beyond the scope of this column to discuss them. One should work with your doctor on this. All of the available medications have different risks and benefits.

In summary, high blood pressure is known as the silent killer since it rarely causes symptoms.  Lowering your blood pressure can reduce your risk of complications including stroke, heart attack and heart failure. A low-salt diet is a key lifestyle change to help prevent elevate blood pressure from turning into high blood pressure and help lower high blood pressure.

Key References

1. Center for Disease Control Hypertension Website – http://www.cdc.gov/bloodpressure/
2. High Blood Pressure Guideline – http://www.nhlbi.nih.gov/files/docs/guidelines/express.pdf
3. Lew EA, Wilber J: Report on the “1979 build and blood pressure study” supplementary observations. Record of Society of Actuaries. 1982 8{4}1179-80
4. Dash Diet – https://www.nhlbi.nih.gov/health/health-topics/topics/dash
5. Salt added to fresh chicken – http://blog.fooducate.com/2011/07/22/are-you-buying-meat-but-paying-for-salt-water/