High Blood Pressure Facts and Myths

Blood pressure is the force of blood against the walls of arteries. It is created by the heart pumping blood round the body. Every year, doctors took blood pressure readings on millions of people, the accumulated data clearly show that high blood pressure, also known as hypertension, has been a major threat to health. Globally, about one billion people have hypertension, it is the leading cause of cardiovascular diseases worldwide, and the problem is still growing. However, hypertension is a widely misunderstood medical condition, even though a large population is living and struggling with it, many people are not knowledgeable or aware of what to do. Education and awareness are key elements in battling hypertension. Here are some facts and myths about high blood pressure.



Blood Pressure Categories Systolic (mm Hg)   Diastolic (mm Hg) Indications
Hypotension < 90 or < 60 Low blood pressure
Normal 90 - 119 and 60 - 79 Blood pressure reading is ideal and healthy
Prehypertension 120 – 139 or 80 – 89 A normal blood pressure reading but it is a little higher than it should be, and thus should try to lower it
Hypertension Stage 1 140 – 159 or 90 – 99 High blood pressure
Hypertension Stage 2 160 - 179 or 100 - 109 High blood pressure
Hypertensive Crisis > 180 or > 110 Emergency care needed
Blood pressure is typically recorded in two numbers: systolic pressure (top) over the diastolic pressure (bottom). The optimal blood pressure is below 120/80 mm Hg, which indicates the blood circulation is in good condition. Clinical evidence suggests that controlling the two readings is important to prevent heart attack and stroke, and both should be within the recommended healthy levels. However, doctors tend to pay more attention to the top reading than the bottom reading, because a rise systolic blood pressure will become a major risk factor for cardiovascular disease in people over 50 years old. As we get older, systolic blood pressure tends to increase, while diastolic blood pressure tends to be the more constant figure. A high systolic blood pressure but normal or low diastolic blood pressure is called isolated systolic hypertension (ISH), which is most common in adults over 65, and yet the least treated form of hypertension. Nevertheless, if either reading is consistently above normal level, talk to your doctor for the best way to do this.

Since blood pressure changes according to posture, exercise, stress or sleep condition, one single high reading may not be necessarily mean that you have hypertension. Doctors usually measure several readings over time, and you may need to monitor your blood pressure at home before diagnosing with hypertension. If you get a high reading, it is advised to measure at least twice on separate days to sure whether your blood pressure is consistently high. You should also avoid caffeine and physical activity several hours before the measuring in order to get an accurate reading. For a healthy adult, even your blood pressure is normal (below 120/80 mm Hg), the American Heart Association recommends having regular blood pressure screening every 1-2 years.

Most of the time, high blood pressure appears little warning and few symptoms, people may not realize it for years until struck by a disabling stroke or a fatal heart attack, that’s why it is known as a “silent killer.” Long standing high blood pressure results in hardening and narrowing of the arteries, makes the heart overload, which in turn affect the blood supply of the body, and cause permanent damages to organs like heart, brain, eyes and kidneys. Hypertension is a major risk factor for heart attack, heart failure, stroke, bleeding from large blood vessel, chronic kidney disease, dementia and blindness. Medical professionals consider a reading above 120/80 mm Hg as elevated blood pressure for most people. A national survey showed that a systolic blood pressure of 115 mm Hg or above is sufficient to generate damage to the arteries and organs, and for every 20 mm Hg rise in systolic blood pressure and 10 mm Hg rise in diastolic blood pressure, the risk of cardiovascular disease are doubled. In the United States, 77% of patients who treated for a first stroke, 69% of patients who have a first heart attack, and 74% of patients with congestive heart failure have blood pressure over 140/90 mm Hg.

It is true that blood pressure increases with age, men over age 45 and women over age 55 are more likely to develop hypertension. But hypertension is not just an old age problem anymore, more and more young people are diagnosed with hypertension. This is mainly due to a modern unhealthy lifestyle that weakens the blood vessels. Prehypertension, a slightly elevated blood pressure 120-139/80-89 mm Hg, is common in young adults. Prehypertension is a warning sign that if you don't make lifestyle changes, such as more physically active and healthier diet, a “real” hypertension will develop in the future. A study found that maintaining or achieving normal blood pressure by age 55 resulted in the lowest lifetime risk to cardiovascular diseases. People with prehypertension should check the blood pressure more frequently, so that any increase can be regulated.

Even if you are in at-risk group, or you have family members with high blood pressure, you can still prevent high blood pressure. High blood pressure is linked to a group of risk factors, you can take certain preventive measures to reduce the chance of developing it, such as healthy diet, regular exercise, controlling body weight, reducing stress, no smoking, moderate drinking and appropriate medical prescriptions.

This isn't always true. Although poor lifestyles such as a high-fat diet or physically inactive tend to increase both cholesterol and blood pressure levels, but it is possible to have high cholesterol but without hypertension. You should check the blood pressure and cholesterol regularly, if both are up, then it is particularly not favor to your blood vessels. Generally, hypertension makes a greater risk of having cardiovascular problems than high cholesterol. Because if your ratio of HDL cholesterol (good) to LDL cholesterol (bad) is healthy, then your risk is not so great, however, high blood pressure always put stress on the walls of blood vessels, that can facilitate plaque building up to block the vessels and eventually leads to heart attack or stroke.

In some people, too much salt can cause their body to retain fluid, which increases blood pressure. Controlling salt intake is more than cutting it in your cooking, you should also consider the hidden sources, such as tomato sauce, soups, condiments, monosodium glutamate (MSG), canned foods, processed meats and frozen foods. In addition, high salt intake is only one of the many factors that can affect blood pressure, other are family history, age, obesity and certain diseases. You should consult your doctor for the best preventive measures.

Poor diet and lifestyles, such as a high salt diet, lack of exercise or overweight, can certainly increase your risk of having high blood pressure. However, there are other risk factors that should be considered:

  • Age: blood pressure tends to increases with age
  • Race: high blood pressure is particular common in blacks
  • Family history: high blood pressure tends to run in families
  • Smoking or drinking too much
  • Nutritional problems: such as potassium or vitamin D deficiency
  • Stress: stress leads to a temporary but dramatic increase in blood pressure
  • Chronic conditions: such as high cholesterol, diabetes, kidney disease and sleep apnea.

If you belong to an at-risk group, you should have regular blood pressure checks and ask your doctor for proper preventive measures.

Remember that wine is a kind of alcohol, heavy and regular consumption makes blood pressure rise. Heavy drinking contributes to high triglycerides, cancers, obesity, alcoholism, suicide and accidents, and it can be highly addictive too. You should drink in a moderate way, no more than two drinks per day for men and one drink per day for women. Generally, one drink equals a 12-ounce beer, a four-ounce glass of wine, 1.5 ounces of 80-proof liquor, or one ounce of hard liquor (100-proof).

Most people with high blood pressure may experience no or few obvious symptoms, so they may not be too concerned. It should be noted that persistently elevated blood pressure damages the blood vessels, makes the heart work hard, over time this creates a negative effect to the body, resulting in severe health problems such as stroke, blindness, kidney failure, and heart failure. The later it treats, the more serious its complications can become. In the United State, among those who have high blood pressure, over 20% are unaware of their condition, for those who known, only 69.1% are under treatment. There is no healthy level of high blood pressure, you should be responsible to keep your blood pressure in optimal level (below 120/80 mm Hg), and don't assume that symptoms will alert you to the problem.

Hypertension is commonly known as the “silent killer,” because its warning signs or symptoms are hard to identify. People might think that hypertensive individuals are more nervous and hyperactive, they tends to develop headache, dizziness, flushed face, sweating, heart beating, poor sleeping and nose bleeding easily, but all of these are not necessarily indicated an increasing high blood pressure, none of these traditional signs is reliable for warming. A slight increase in blood pressure can’t make you feeling ill, the symptoms may be attributed to other health concerns. Actually, when patients talk about feeling stressed or having a headache when the pressure goes up, it is usually the stress or the pain from the headache that causes the blood pressure rise, not the other way around. Even if blood pressure increases to dangerous levels (180/110 mm Hg or higher), some patients may have no symptom at all. The only way to know your blood pressure level is to have it measured.

If you have hypertension, 140/90 mm Hg or above, you should probably buy a machine to monitor your blood pressure regularly. This also helps you realize the treatment progress, and even alert you to potential complications. Since the damages of hypertension occur over years, not weeks or days, once your blood pressure is stable, a weekly check is often enough. If your doctor have another suggestion, do it accordingly as he is the best person to guide you the frequency of checking. It is important to measure at the same time, such as morning and evening, or as your doctor recommended. Keep track of your average blood pressure and then report to your doctor for discussion.

Blood pressure can fluctuate dramatically throughout the day, it is essential to measure it at the same time and under the same conditions each time. Basically, the ideal time to check your blood pressure is in the morning just after waking up, before breakfast and before any activity or exercise. You should relax for about 5 minutes before measuring. The following situations may cause substantial variations in blood pressure readings and should therefore be avoided at least 30 minutes before measuring blood pressure:

  • exciting or tense
  • taking a bath
  • during exercise or soon after exercising
  • cold environment
  • within one hour after eating
  • after drinking coffee, tea or other stimulating beverages
  • after smoking
  • a full bladder

** Blood pressure is usually lower than usual after taking a bath and after drinking alcohol.


If you have hypertension, it is necessary to see your doctor on a regular basis. Every time when you visit your doctor, you better wear a short-sleeve shirt, so that the blood pressure cuff can fit around your arm properly. You should avoid caffeinated food and drinks, and also use the toilet in advance. During the appointment, report any symptoms, your doctor may ask about your other medical conditions such as heart disease, kidney disease or diabetes. Tell about medications you used such as herbs, supplements and OTC medications, and also about your diet, work, daily activities and stressful events recently. Give your home-monitoring blood pressure details and discuss them with your doctor.

Many patients get nervous at doctors’ office, which can make blood pressure rise, a condition known as “white-coat hypertension.” About 25% of patients show at least 20 mm Hg higher than they would when they are checked by doctors, however, repeatedly high readings should indicate a non-situational condition. It is suggested to take your blood pressure readings at home several times and then share the results with your doctor. Your doctor may recommend you to undergo an Ambulatory Blood Pressure Monitor (ABPM) for 24 hours to determine your “real” average blood pressure. It should be noted that modern digital monitors need to be calibrated every 6 to 12 months to stay accurate, while mercury sphygmomanometers, the older instruments used in doctors’ office, don't need calibrating. It is better to take the monitor to your doctor’s office, and compare the readings for setting.

Yes, it could be. Therefore it is advised to measure on both arms in the beginning, the arm with higher pressure should then be chosen for the continuous monitoring. Generally, a small difference in blood pressure readings between arms isn't a health concern. However, if more than 20 mm Hg (top number) or more than 10 mm Hg (bottom number) show up repeatedly between two arms, it may be a sign of an underlying problem, such as peripheral artery disease, kidney disease, diabetes or heart defects.

  • Severe headache, accompanied by confusion and blurred vision
  • Breathing difficulty
  • Nausea and vomiting
  • Severe anxiety
  • Blood in urine
  • Pounding in chest, neck or ears

The above symptoms may indicate that you have a hypertensive crisis and can be associated with life-threatening complications. You require a hospital treatment.




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