Understanding blood pressure levels

Blood pressure levels chart | High blood pressure | Low blood pressure | When to see a doctor

Blood pressure is the force of blood against blood vessel walls as the blood moves through the circulatory system. Blood pressure rises and falls throughout the day and varies depending on our activity. It is important to know what your blood pressure runs, as abnormally high or low blood pressure could indicate underlying health conditions. Let’s take an in-depth look at blood pressure levels to understand what it means if your blood pressure is high or low.    

What is the normal blood pressure range?

It’s normal for blood pressure levels to fluctuate throughout the day based on what you’re eating, how stressed you are, and whether you’re exercising. Blood pressure is measured using two numbers: systolic (top number) and diastolic (bottom number). Systolic blood pressure measures the pressure in arteries when the heart beats, and diastolic blood pressure measures the pressure in arteries when the heart rests between beats. Here’s a blood pressure chart from the American Heart Association (AHA) to help you better understand blood pressure measurements: 

Normal blood pressure readings are below 120/80 mmHg and above 90/60 mmHg. Blood pressure readings outside this range may indicate high blood pressure (hypertension) or low blood pressure (hypotension). Both systolic and diastolic pressure numbers are important. Still, systolic blood pressure (top number) is given more attention because high systolic pressure may be associated with an increased risk of stroke and cardiovascular disease.   

Blood pressure by age and gender

As people age, the risk of getting high blood pressure increases. Adults 19-40 years old will have blood pressure levels that fluctuate between 90-135/60-80 mmHg. The latest hypertension guideline from 2017 labels these younger individuals as hypertensive if the systolic blood pressure range is 130-139 or diastolic blood pressure range is between 80-89, however, the treatment depends on their calculated risk of cardiovascular disease.

Women

According to the American Heart Association (AHA), blood pressure ranges are the same for men and women. Women and men have about the same chance of developing high blood pressure at some time in their lives. Although high blood pressure is not directly caused by gender, the AHA explains that blood pressure can be affected by pregnancy, birth control, or menopause.

Birth control pills may increase blood pressure in women. This is more likely to occur in women who are overweight, have kidney problems, or have family members with high blood pressure.

Seniors

Blood pressure ranges are the same for adults of all ages, according to the new guidelines. Whereas previously older adults were considered to have high blood pressure at 150/80, now high blood pressure is considered to be 130/80, regardless of age. Many people who previously were not diagnosed with high blood pressure now fall into categories of high blood pressure.

According to the National Institute on Aging, older adults often experience a condition called isolated systolic hypertension. This occurs when the systolic is 130 or higher, and the diastolic is less than 80. This type of high blood pressure occurs due to stiffening of major arteries, which happens with age. Isolated systolic hypertension is the most common form of high blood pressure in older adults. It can cause serious health problems as well as shortness of breath (even with light activity), dizziness when standing, and falls. Seniors should see their healthcare provider on a regular basis to check blood pressure, as well as check blood pressure regularly at home. Isolated systolic hypertension may require more than one type of blood pressure medication. 

RELATED: What’s a normal heart rate?

High blood pressure range

Elevated blood pressure is defined as a blood pressure of 120-129/<80, and stage 1 high blood pressure is defined as a blood pressure of 130-139 systolic or 80-89 diastolic.

Nearly half of American adults have hypertension, or high blood pressure, and only 1 in 4 adults have the condition under control, according to the Centers for Disease Control and Prevention (CDC). Statistics from the World Health Organization (WHO) reveal that an estimated 1.13 billion people have high blood pressure globally and that it’s a major cause of premature death. 

High blood pressure negatively affects the body in many ways. Hypertension causes the heart to work harder than normal; it can damage arteries, enlarge the left ventricle of the heart, and even cause cognitive impairment, strokes, and heart failure. When blood pressure is elevated, it constricts blood vessels, causing the organs that need blood and oxygen to be damaged. This can damage retinas in the eyes causing blindness, cause kidney failure, and erectile dysfunction in men.

For example, if your blood pressure is 135/60, it would be considered stage 1 hypertension because the top number falls between 130 and 139. 

RELATED: Heart disease statistics

Symptoms of high blood pressure

Often high blood pressure is asymptomatic.  It typically doesn’t cause symptoms until it leads to a serious health problem like a stroke or heart attack. This is why hypertension is  referred to as the “silent killer.” When it causes symptoms or side effects, people may experience one or more of the following:   

• Dizziness
• Headaches
• Facial flushing
• Chest pain
• Confusion
• Nosebleeds
• Difficulty breathing
• Irregular heartbeat
• Blood in the urine 

If you have any of these symptoms, it doesn’t necessarily mean that your blood pressure is too high. Some people will have one or more of these symptoms for unrelated reasons, so it’s always a good idea to check your blood pressure on a regular basis. 

Causes of high blood pressure

Some people are more at risk of having hypertension over their lifetime. In general, high blood pressure levels occur slowly over time, though something like anxiety can cause short-term spikes in blood pressure. Here are the most common risk factors and causes of high blood pressure:   

• Diabetes
• Obesity (a BMI >30)
• Sedentary lifestyle
• Unhealthy diet
• Smoking
• Drinking too much alcohol
• Family history of high blood pressure
• Older age 

Even though blood pressure is considered high if it’s 130/80 mmHg or above, it’s also possible to have a high top blood pressure number and a normal low blood pressure number. This is a condition called isolated systolic hypertension, mainly caused by underlying medical conditions like diabetes, hyperthyroidism, and heart valve problems. A high bottom number on a blood pressure reading is likely the result of consuming too much sodium, obesity, drinking too much alcohol, and not getting enough physical exercise.  If blood pressures continue to be elevated, regardless of the cause, the body benefits from medication to normalize the blood pressure.

High blood pressure treatments

Treating high blood pressure often involves a combination of lifestyle changes and medications. Here are the most common hypertension treatments: 

RELATED: ACE inhibitors vs. beta blockers

Note: The CDC includes hypertensive patients in the high-risk groups for contracting COVID-19 or developing coronavirus complications.

Lifestyle changes can help lower blood pressure levels and benefit the overall health of the patient. Some effective changes include:

• Exercising moderately 30 minutes most days of the week. 
• Eating a healthy diet.
• Limiting excessive salt intake. No more than 2000 mg of sodium per day. 
• Maintaining a healthy body weight (BMI 20-25).
• Managing stress. Consider incorporating meditation or yoga.
• Limiting alcohol use.  No more than 14 alcoholic drinks/week for men or 7 alcoholic drinks/week for women.
• Quitting smoking. 

Low blood pressure range

The prevalence of low blood pressure is unknown, but we know it’s a common condition that affects people worldwide. Normal blood pressure is defined as a systolic less than 120 and a diastolic less than 80, and low blood pressure is considered to be 90/60 or lower. 

According to the American Heart Association, “Within certain limits, the lower your blood pressure reading is, the better. There is also no specific number at which day-to-day blood pressure is considered too low, as long as none of the symptoms of trouble are present.” 

In other words, one person may have a low blood pressure of 85/55 and feel just fine, while another may have the same blood pressure and have symptoms. When one or more of these symptoms (mentioned below) are involved, the person’s low blood pressure can be dangerous. Low blood pressure can affect the body in many ways. 

Symptoms of low blood pressure

Here are the most common symptoms of hypotension which routinely occur upon standing:

• Dizziness
• Weakness
• Lightheadedness
• Confusion
• Blurry vision
• Nausea
• Tiredness
• Cold and sweaty skin
• Quick and shallow breathing 

Sudden drops in blood pressure can cause any of these symptoms. Extreme drops in blood pressure can cause your body to go into shock. Chronically low blood pressure can be dangerous because the body won’t get enough oxygen to the heart and brain, which may cause permanent damage. Regularly checking your blood pressure with a home blood pressure monitor is essential.    

Causes of low blood pressure

Blood pressure level below 90/60 mmHg is considered low. “The most common reasons for lowered blood pressure are low blood volume (think: dehydration or blood loss), over treatment of high blood pressure, or taking certain medications that can lower blood pressure,” says Susan Besser, MD, a primary care provider who specializes in Family Medicine at Mercy Medical Center in Baltimore. 

Here are some other common reasons for sudden drops in blood pressure levels and chronic hypotension:   

• Pregnancy
• Certain medications, like heart medicines or depression medications
• Certain health problems like heart disease or thyroid disease
• Trauma that results in blood loss or blood infection
• Heavy menstrual periods
• Extreme changes in body temperature 

Some people are more likely to have low blood pressure levels based on their age, sex, and medical history. Here are the top risk factors for getting hypotension:

• Older age
• Being pregnant
• Having diabetes
• Having heart problems
• Having liver disease
• Having hormonal imbalances
• Having vitamin and/or nutrient deficiencies 

Low blood pressure treatments

The right treatment plan for hypotension will vary depending on the person and what’s causing their low blood pressure. Consult with a healthcare provider. Leading a healthy lifestyle and staying hydrated can help fix low blood pressure. Rarely, patients require medication to elevate their blood pressure in the normal range: 

Some lifestyle changes that can also naturally raise blood pressure, include:

• Drinking plenty of water
• Increasing your salt intake if approved by a provider
• Consuming less alcohol
• Avoiding standing for long periods of time
• Consuming small amounts of caffeine if approved by a provider  
• Eating frequent, small, low-carb meals  

RELATED: Blood pressure treatments and medications

Dangerous blood pressure levels—when to see a doctor?

If you have two elevated blood pressure readings, you should see your provider for advice.  If your blood pressure is at the life-threatening level of 180/120, then you need emergent care to address this hypertensive crisis. If your blood pressure goes above 180/120 mmHg and you’re having chest pain, signs of a stroke, or heart attack, you should go to the ER, says Dr. Besser. Dangerous blood pressure levels that go unchecked can also cause:

• Memory problems
• Heart failure
• Aneurysms 
• Sudden loss of kidney function
• Pregnancy complications
• Blindness 

On the other hand, sudden drops in blood pressure can be dangerous, especially for older adults who are more prone to weakness, dizziness, and fainting. Having one abnormal low blood pressure reading that’s below 90/60 mmHg is okay, but if you keep experiencing low blood pressure, then visit your doctor’s office.