When doctors take a person’s blood pressure, they measure the force that blood exerts on the walls of the arteries as it flows through them.
If blood pressure is too high for too long, it can cause serious damage to the blood vessels.
This damage can result in a range of complications, some of which can be life threatening. They include heart failure, vision loss, stroke, kidney disease, and other health problems.
There are ways of managing high blood pressure, or hypertension. High blood pressure often does not cause symptoms, but regular screening can help a person know if they need to take preventive action.
In the United States, around 75 million people, or 29% of the population, have high blood pressure, according to the Centers for Disease Control and Prevention (CDC).
In this article, we look at the causes of high blood pressure and how to treat it. We also explain the blood pressure measurements that health authorities consider to be healthy and too high.
What is high blood pressure?
The heart is a muscle that pumps blood around the body. As it travels, the blood delivers oxygen to the body’s vital organs.
Sometimes, a problem in the body makes it harder for the heart to pump the blood. This could happen, for example, if an artery becomes too narrow.
Persistent high blood pressure can put a strain on the walls of the arteries. This can lead to a variety of health problems, some of which can be life threatening.
Diastolic and systolic pressure
There are two parts to a blood pressure measurement:
Systolic pressure: This is the blood pressure when the heart contracts.
Diastolic pressure: This is the blood pressure between heartbeats.
If blood pressure is 120/80 mm Hg, it means that the systolic pressure is 120 mm Hg and the diastolic pressure is 80 mm Hg.
High blood pressure chart
The chart below shows measures for normal and high blood pressure, according to the American Heart Association(AHA).
Doctors measure blood pressure in millimeters of mercury (mm Hg).
Systolic pressure measures the pressure in the arteries as the heart contracts and is the top number on a blood pressure reading. Diastolic, which is the lower number, represents the blood pressure when the heart is resting between beats.
|
Systolic (mm Hg) |
Diastolic (mm Hg) |
|
|
Normal |
Below 120 |
Below 80 |
|
Elevated (hypertension) |
120–129 |
Below 80 |
|
Stage 1 hypertension |
130–139 |
80–90 |
|
Stage 2 hypertension |
140 or above |
90 or above |
|
Hypertensive crisis |
Over 180 |
Over 120 |
Signs and symptoms
Most people with high blood pressure will not experience any symptoms, which is why people often call hypertension the “silent killer.”
However, once blood pressure reaches about 180/120 mm Hg, it becomes a hypertensive crisis, which is a medical emergency.
At this stage, a person may have:
- a headache
- nausea
- vomiting
- dizziness
- blurred or double vision
- nosebleeds
- heart palpitations
- breathlessness
Anybody who experiences these symptoms should see their doctor immediately.
Symptoms in women
Hormonal factors mean that the risk of high blood pressure may be different in males and females.
Factors that can increase the risk of high blood pressure in females include:
- pregnancy
- menopause
- the use of birth control pills
During pregnancy, high blood pressure can be a sign of preeclampsia, a potentially dangerous condition that can affect the woman and her unborn baby.
Symptoms of preeclampsia include:
- headaches
- vision changes
- abdominal pain
- swelling due to edema
All women should follow the guidelines for screening and attend all health checks, especially during pregnancy.
Symptoms in teens
Teenagers can develop high blood pressure due to obesity or an underlying medical condition.
Possible medical factors include:
- aspects of metabolic syndrome, such as type 2 diabetes
- kidney disease
- endocrine disease, which affects the hormones
- vascular disease, which affects the blood vessels
- a neurological condition
These conditions may have symptoms of their own. The symptoms of high blood pressure, if they occur, will be the same as for other groups.
Symptoms in children
High blood pressure can affect children. Having obesity and diabetes increases the risk, but it can also be a sign of:
- a tumor
- heart problems
- kidney problems
- thyroid problems
- a genetic condition, such as Cushing’s syndrome
As with adults, high blood pressure often does not cause symptoms in children.
However, if symptoms do occur, they may include:
- a headache
- fatigue
- blurred vision
- nosebleeds
They may also have signs of another condition.
Symptoms in babies
Newborns and very young babies can sometimes have high blood pressure due to an underlying health condition, such as kidney or heart disease.
Symptoms may include:
- a failure to thrive
- seizures
- irritability
- lethargy
- respiratory distress
Other symptoms will depend on the condition that is causing the high blood pressure.
Causes
High blood pressure can occur when certain changes happen in the body or if a person is born with specific genetic features that cause a health condition.
It can affect people with:
- obesity
- type 2 diabetes
- kidney disease
- obstructive sleep apnea
- lupus
- scleroderma
- underactive or overactive thyroid
- congenital conditions, such as Cushing’s syndrome, acromegaly, or pheochromocytoma
Sometimes, there is no apparent cause. In this case, a doctor will diagnose primary hypertension.
Consuming a high fat diet, carrying excess weight, drinking a lot of alcohol, smoking tobacco, and the use of some medications also increase the risk.
How to lower blood pressure
Treatment will depend on several factors, including:
- how high the blood pressure is
- the risk of cardiovascular disease or a stroke
The doctor will recommend different treatments as blood pressure increases. For slightly high blood pressure, they may suggest making lifestyle changes and monitoring the blood pressure.
If blood pressure is high, they will recommend medication. The options may change over time, according to how severe the hypertension is and whether complications arise, such as kidney disease. Some people may need a combination of several different medications.
Diet
Managing the diet can be an effective way of both preventing and treating high blood pressure.
Plant-based foods
A healthful, balanced diet includes plenty of fruits and vegetables, vegetable and omega oils, and good quality, unrefined carbohydrates, such as whole grains. People who include animal products in their diet should trim all the fat off and avoid processed meats.
Lowering salt intake
Experts recommend reducing salt consumption and increasing potassium intake to manage or prevent high blood pressure. Limiting salt intake to less than 5-6 grams
per day could help improve cardiovascular health and reduce systolic blood pressure by 5.6 mm Hg in people with hypertension.
Healthful fats
In moderation, plant sources of fats, such as avocados, nuts, olive oil, and omega oils, can be healthful. People should limit their intake of saturated fats and trans fats, common in animal-sourced and processed foods.
The DASH diet
Health expert recommend the DASH diet for people with high blood pressure. The DASH diet focuses on an eating plan that emphasizes whole grains, fruits, vegetables, nuts, seeds, beans, and low-fat dairy products.
Alcohol
Some studies indicate that consuming some alcohol may help lower blood pressure. However, others report the opposite, noting that even drinking a moderate amount might increase blood pressure levels.
People who regularly drink more than moderate amounts of alcohol will almost always experience elevated blood pressure levels.
Caffeine
Studies into the relationship between caffeine and blood pressure have produced conflicting results. A report published in 2017 concluded that a moderate intake of coffee appears to be safe for people with high blood pressure.
Home remedies
The AHA recommend a range of lifestyle adjustments that can help reduce blood pressure, such as:
- managing stress
- quitting smoking
- eating healthfully
- getting exercise
- following any treatment plan the doctor prescribes
Discuss any planned lifestyle changes with a healthcare professional before introducing them.
Regular exercise
The AHA note that most healthy people should do at least 150 minutes of moderate intensity physical exercise a week. This could be 30 minutes — or three lots of 10 minutes a day — on 5 days of the week.
This amount of exercise is also appropriate for people with high blood pressure.
However, a person who has not exercised for a while or who has a new diagnosis should talk to their doctor before starting a new physical activity program to ensure the choices they make are suitable for them.
Losing weight
Studies have revealed that losing as little as 5–10 pounds in weight can help reduce blood pressure.
Weight loss will also improve the effectiveness of blood pressure medications.
Ways of achieving and maintaining a healthy weight include:
- getting regular exercise
- following a diet that emphasizes plant-based foods and limits the intake of fat and added sugars
Sleep
Increasing sleep alone cannot treat hypertension, but too little sleep and poor sleep quality may make it worse.
A 2015 analysis of data from a Korean national health survey found that people who had less than 5 hours of sleep per night were more likely to have hypertension.
Natural remedies
According to the National Center for Complementary and Integrative Health (NCCIH), the following may lower high blood pressure:
- meditation, yoga, qi gong, and tai chi
- biofeedback and transcendental meditation
- supplements such as garlic, flaxseed, green or black tea, probiotics, cocoa, and roselle (Hibiscus sabdariffa)
The NCCIH add, however, that there is not yet enough evidence to confirm that these can make a difference.
They also warn that:
Some supplements can have adverse effects. They may raise blood pressure or interact with medications.
Meditation and exercise therapies are usually safe, but some poses may not be suitable for people with high blood pressure. Anyone who is considering an alternative therapy should speak to their doctor first.