Blood pressure is the force, or pressure, the blood exerts on artery walls. It's measured in millimeters of mercury (mmHg). Blood pressure consists of two numbers, systolic and diastolic. Systolic blood pressure, the higher number, is the pressure measured as the heart beats. Diastolic blood pressure, the lower number, is the pressure measured as the heart relaxes between beats. For example, if your blood pressure is 120 over 80, then 120 is the systolic and 80 is the diastolic.
Healthy and Elevated Blood Pressure Values
A normal, or healthy, blood pressure is a systolic value less than 120 and a diastolic value less than 80. Elevated blood pressure can fall into two categories, pre-hypertension and hypertension. The word hypertension is the clinical term for high blood pressure. Pre-hypertension is a slight rise in blood pressure, before the disease is fully diagnosed, and occurs when systolic blood pressure is between 120 and 130 or a diastolic blood pressure is between 80 and 89. Hypertension, the full-blown disease, is diagnosed with a systolic blood pressure over 140 or a diastolic blood pressure over 90.
For people who already have diabetes or kidney disease, hypertension may be diagnosed before blood pressure reaches 140 or 90. These diseases are connected to hypertension and together put someone at a much greater health risk.
Dangers of High Blood Pressure
When your blood pressure is high, it makes your heart work too hard. In addition, the force of the blood can harm your arteries. If you don't bring it down, high blood pressure can lead to coronary artery disease, heart failure, kidney disease, dementia, stroke and damage to the retina of the eye.
Another danger of high blood pressure is its nature of being a silent condition. It doesn't have warning signs or symptoms, and once it occurs, it usually lasts a lifetime. Even minor increases in your systolic or diastolic blood pressure values can damage your heart and other organs, necessitating that you take action to control it. The higher your blood pressure is above normal, the greater your health risk is.
Risk Factors for High Blood Pressure
Kidney disease, elevated blood glucose levels, tumors, hormonal disorders, some medications and a complicated pregnancy account for only 10 percent of hypertension cases. The cause of the remaining cases is unknown. However, there are certain factors that increase someone's risk of developing the disease, such as being male, African American and older than 45 years for men and older than 55 years for women.
While you can't change these factors about yourself, other factors, called lifestyle factors, increase your risk of developing hypertension and can be changed. They are smoking, stress, high sodium intake, overweight and obesity, physical inactivity and excessive alcohol consumption.
Lowering Blood Pressure through DASH
Following the Dietary Approaches to Stop Hypertension diet, called the DASH diet, can lower your systolic blood pressure by 8 to14 mmHg. This diet focuses on fruits and vegetables, whole grains, fish, lean poultry, nuts, seeds and beans. It is low in total, saturated and trans fats; cholesterol; red meat; sweets; and sweetened beverages. The DASH diet can help you lose weight as well, which lowers blood pressure independently.
Lowering Blood Pressure through Reducing Sodium
Another approach to lower your blood pressure is reducing the amount of sodium you eat. Sodium is a component of salt. The average American eats 3,300 mg of sodium a day. However, the tolerable upper intake level of sodium, or the level above which side effects may occur, is 2,300 mg a day. This is found in 1 tsp. of salt. Limiting your sodium intake to 2,300 mg can lower your blood pressure by 2 to 8 mmHg. Further reductions in sodium intake to 1,500 mg a day, about two-thirds of a teaspoon of salt, is recommended and can lower your blood pressure further.
The winning combination to lower your blood is following both the DASH and low-sodium diets.
References
- "Archives of International Medicine"; Effects of reduced sodium intake on hypertension control in older individuals: results from the Trial of Nonpharmacologic Interventions in the Elderly (TONE); L J Appel; March 2001
- "American Journal of Clinical Nutrition"; Blood pressure and urinary sodium in men and women: the Norfolk Cohort of the European Prospective Investigation into Cancer; K T Khaw; November 2004
- "Clinical Cardiology"; A dietary approach to prevent hypertension: A review of the dietary approaches to stop hypertension (DASH) study; F M Sacks; July 1999
