THE TWO NUMBERS
Blood pressure is divided into two parts, systolic and diastolic. Systolic is the pressure of the heart beating. Diastolic is the pressure of the heart and vessels filling. When blood pressure numbers are written out, like "120/80," 120 is the systolic pressure and 80 is the diastolic pressure. The unit of measurement for blood pressure is millimeters of mercury, written as "mm/Hg."
HEALTHY BP
Experts consider healthy blood pressure numbers to be 115/75 mm/Hg. The reason? They found that the risk of cardiovascular disease doubles at each increment of 20/10 mm/Hg over 115/75 mm/Hg. Even small jumps in blood pressure numbers increase the risk of stroke and heart attack.
For many years, high diastolic pressure was considered even more of a threat than high systolic pressure. That thinking has changed somewhat, but high diastolic numbers could still mean organ damage in your body� especially for individuals under 50.
A person's blood pressure can naturally vary throughout the day�even between heartbeats. However, if the numbers are consistently high (over 120 systolic and 80 diastolic), after multiple visits to your healthcare practitioner, you may have either pre-hypertension or high blood pressure.
THE NEW CATEGORY
Pre-hypertensive is a new category that was announced May 2003 by the National Heart, Lung, and Blood Institute (NHLBI) that includes an estimated 45 million American adults with blood pressures of 120-139 over 80-89. People who are classified as prehypertensive are at high risk of developing hypertension and should make lifestyle modifications to reduce their risk of developing hypertension in the future.
CAUSES OF HIGH BP
The reasons for hypertension aren't always clear. However, there are lifestyle factors that contribute to high blood pressure that you can change:
Body type: Weight isn't always a reliable indicator of whether or not you'll have high blood pressure�but the type of weight is. Lean body mass�muscle�doesn't increase blood pressure levels the way that fat can. However, fat body mass, especially fat around your middle, can contribute to high blood pressure.
Sedentary lifestyle: Too often, many of us sit down all day at work, and then sit down all night at home. Over time, this inactivity usually leads to weight gain, making the heart work harder to pump blood through the body. In a way, it almost seems contradictory, but inactivity usually leads to higher heart rates.
Sodium intake: Sometimes it's hard to believe how much salt there is in processed foods. However, salt intake in itself is not necessarily bad. For people with a history of congestive heart failure, ischemia, and high blood pressure, sodium is definitely out. For those individuals, it leads to more water retention, which increases blood pressure. (Salt's effect on water retention is one reason that so many sports drinks have fairly high sodium content�the sodium in the drink prevents your body from sweating out too much water.) But, for healthy individuals, moderate salt intake, especially a mixed mineral salt like sea salt or Celtic salt (good salt should never be white) is fine.
Low potassium intake: Unlike sodium, potassium is a mineral that most Americans get too little of. Potassium helps regulate the amount of sodium in our cells, expelling excess amounts through the kidneys. Low levels of this mineral can allow too much sodium to build up in the body.
Heavy alcohol intake: Having three or more alcoholic drinks a day (two or more for women) nearly doubles an individual's chance of developing high blood pressure. Over time, heavy drinking puts a lot of stress on the organs, including the heart, liver, pancreas and brain.
Unhealthy eating: Eating a lot of processed or fatty foods contributes to high blood pressure. Adapting a diet that is rich in fruits and vegetables, whole grain products, fish, nuts and magnesium and potassium (like the Dietary Approaches to Stop Hypertension, known as the "DASH" diet) can bring it back down.
Smoking: If you smoke, stop. Smoking damages the heart and arteries�period. Nicotine constricts blood vessels, increases heart rate, and raises blood pressure. This in turn, increases hormone production and adrenaline levels, further stressing the body. As if that weren't bad enough, the carbon monoxide in cigarette smoke replaces the oxygen in the blood, making the heart work even harder to make up the difference. Since the effect of a single cigarette can last for an hour, smoking throughout the day leads to continuously revved-up blood pressure. Some of these factors might sound like a lot to overcome. The important thing to remember is that all of these behaviors are changeable. If you have high blood pressure, modifying any of these can significantly lower blood pressure as part of an overall plan.
CONCLUSION
Make no mistake about it: high blood pressure is dangerous. It is the number one modifiable cause of stroke. The higher the blood pressure, the greater is the chance for heart attack, heart failure, stroke and kidney disease. In some cases, it can cause blindness. Just lowering blood pressure reduces the chance of stroke by 35 to 40 percent. Other conditions, including heart attack and heart failure can be reduced from 25 and 50 percent, respectively.
Even people with normal blood pressure at 55 years of age will have a 90% lifetime risk of developing hypertension. The prevalence of hypertension increases with advancing age to the point where more than half of people 60-69 years of age and approximately three-fourths of those 70 years of age and older are affected.
References:
i "High Blood Pressure" American Heart Association. Available at:
http://www.americanheart.org/presenter.jhtml?identifier=2114. Accessed on January 13, 2005.
2. "Classification of Blood Pressure." National Heart Lung Blood Institute. Available at: http://vvww.nhlbi.nih.gov/guideiines/hvpertension/jnc7full.pdf. Accessed on January 14, 2005.
3. "Risk factors: reduce your risk of developing high blood pressure." MayoClinic.com. Available at: http://www.mayoelinic.com/inyoke,cfrn?id=HI00Q26. Accessed: August 20, 2004.
4 "Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7)." Available at: http://www.nhlbi.nih.gov/guidelines/hypertension/jnc7full.htm. Accessed January 18,2005.