Understanding Blood Pressure – What Is It?
Your blood pressure reading is a measurement of the pressure your blood applies across your artery walls. Your blood pressure changes a little throughout the day; when you relax, your blood pressure lowers, and when you move around or feel stress, your blood pressure increases. But high blood pressure over a long term is associated with serious health risks, including heart, brain, and eye damage. Likewise, chronic low blood pressure sometimes comes with health risks. Fortunately, there are helpful ways to manage both high and low blood pressure.
What Do Blood Pressure Numbers Mean?
Your blood pressure reading comes with two numbers. The first number refers to your systolic blood pressure. The second number refers to your diastolic blood pressure.
"Systolic" refers to "contraction" in Latin. Your systolic blood pressure is the highest blood pressure exerted when your heart beats (contracts), and puts pressure on blood vessels. "Diastolic" is related to the Latin word for "dilate." Your diastolic blood pressure is the lowest blood pressure put on your blood vessels, with your heart at rest between beats, when it dilates (expands). Systolic and diastolic blood pressures are usually easy to record with measurements done with a blood pressure cuff. Blood pressure measurements are recorded as systolic pressure/diastolic pressure in mm Hg; for example, 120/80 mm Hg.
Chart: What Are Normal Blood Pressure Ranges by Age for Men?
Men's average BP ranges vary by age group. The age group with the lowest normal blood pressure reading is men age 31-35 (114.5/75.5). The age group with the highest normal blood pressure reading is men ages 61-65 (143.5/76.5).
Chart: What Are Normal Blood Pressure Ranges by Age for Women?
As with men, women's average BP ranges also vary by age group. The age group with the lowest normal blood pressure reading is different between the systolic and diastolic reading. Women ages 21-25 have the lowest normal diastolic reading (115.5-70.5), while women age 31-35 have the lowest normal systolic reading (110.5/72.5). The age group with the highest normal blood pressure reading is women ages 56-60 (132.5/78.5).
High Blood Pressure Categories
You can divide high blood pressure into five categories, according to guidelines from the American College of Cardiology:
- Normal: Normal blood pressure in adults is any blood pressure below 120/80.
- Elevated: In adults, elevated blood pressure is a systolic reading of 120-129 and a diastolic reading below 80.
- Hypertension stage I: This stage includes blood pressures ranges of 130-139 (systolic) or 80-89 (diastolic).
- Hypertension stage II: This stage includes blood pressures ranges above 140 (systolic) or above 90 (diastolic).
- Hypertensive crisis: Severely elevated blood pressure is defined as greater than 180 and/or 120 and associated with new or worsening organ damage.
What Are the Causes of High Blood Pressure?
Elevated blood pressure increases your risk of chronic high blood pressure as you age. Taking steps to manage your blood pressure helps decrease this risk.
There are also some health conditions that increase your risks of chronic high blood pressure, including obesity and diabetes. Other causes include:
- Genetics/family history
- High-sodium, low-potassium diets
- Lack of exercise
- Alcohol or tobacco abuse
As adults age, their odds of high blood pressure increase, with 90% of Americans forecasted to develop high blood pressure in their lifetimes. Black people tend to develop high blood pressure more often and earlier in life compared to white people. Hispanics, Asians, American Indians, and Pacific Islanders also stand an increased risk of high blood pressure compared to other ethnicities.
What Are the Symptoms of High Blood Pressure?
The only way you can know for sure if you have high blood pressure is by having a nurse or doctor measure it. Monitoring your blood pressure at home also helps keep your blood pressure in check. Most often, high blood pressure is "silent," meaning it has no other signs to warn you, according to the CDC.
What Is a Hypertensive Crisis?
A hypertensive crisis occurs when blood pressure suddenly rises above 180 systolic and/or 120 diastolic. This prompt either a hypertensive urgency or hypertensive emergency.
A hypertensive urgency accounts for about 75% of hypertensive crises. In these cases, a person has high blood pressure, but without any serious accompanying symptoms. A hypertensive emergency requires immediate medical care, as high BP is accompanied by one or more serious symptoms, including:
- Ischemic stroke
- Acute pulmonary edema (left ventricular failure)
What Is the Best Treatment for High Blood Pressure?
Depending on your high blood pressure, lifestyle changes and/or medications may be helpful in maintaining a healthy and normal blood pressure. Some common lifestyle recommendations include:
What Are the Causes of Low Blood Pressure (Hypotension)?
Low blood pressure (hypotension) is generally defined as 90/60 mm Hg (or lower) and is not necessarily unhealthy. Some people always have low blood pressure, so it depends on the person. However, a sudden drop in blood pressure may be a warning sign of more serious health problems. For example, Parkinson's disease can cause problems in your body's "fight-or-flight" signals that can lead to low blood pressure. Other low blood pressure causes include:
- Heart problems
What Are the Symptoms of Low Blood Pressure?
Low blood pressure may not have symptoms. But people may experience some of these symptoms:
- Blurry vision
- Neck or back pain
- Heart palpitations
Some of these symptoms are more common in older adults. However, if a person has a sudden fall in their usual blood pressure, especially with symptoms, may indicate a serious medical condition.
What Is the Best Treatment for Low Blood Pressure?
For most people with low blood pressure, no treatment is needed. However, in some cases your doctor might encourage you to:
- Drink more fluids
- Take blood pressure raising medicines
- Changing your standing/sitting habits