You can have high blood pressure (hypertension) for years without a single symptom. Uncontrolled high blood pressure increases your risk of serious health problems, including heart attack and stroke.
Blood pressure is determined by the amount of blood your heart pumps and the amount of resistance to blood flow in your arteries. The more blood your heart pumps and the narrower your arteries, the higher your blood pressure.
High blood pressure typically develops over many years, and it affects nearly everyone eventually. Fortunately, high blood pressure can be easily detected. And once you know you have high blood pressure, you can work with your doctor to control it.
Most people with high blood pressure have no signs or symptoms, even if blood pressure readings reach dangerously high levels. Although a few people with early-stage high blood pressure may have dull headaches, dizzy spells or a few more nosebleeds than normal, these signs and symptoms typically don't occur until high blood pressure has reached an advanced — even life-threatening — stage.
High blood pressure has many risk factors. Some you can't control. High blood pressure risk factors include:
- Age. The risk of high blood pressure increases as you age. Through early middle age, high blood pressure is more common in men. Women are more likely to develop high blood pressure after menopause.
- Race. High blood pressure is particularly common among blacks, often developing at an earlier age than it does in whites. Serious complications, such as stroke and heart attack, also are more common in blacks.
- Family history. High blood pressure tends to run in families.
Other risk factors for high blood pressure are within your control.
- Being overweight or obese. The more you weigh, the more blood you need to supply oxygen and nutrients to your tissues. As the volume of blood circulated through your blood vessels increases, so does the pressure on your artery walls.
- Not being physically active. People who are inactive tend to have higher heart rates. The higher your heart rate, the harder your heart must work with each contraction — and the stronger the force on your arteries. Lack of physical activity also increases the risk of being overweight.
- Using tobacco. Not only does smoking tobacco immediately raise your blood pressure temporarily, but the chemicals in tobacco can damage the lining of your artery walls. This can cause your arteries to narrow, increasing your blood pressure.
- Too much salt (sodium) in your diet. Too much sodium in your diet can cause your body to retain fluid, which increases blood pressure.
- Too little potassium in your diet. Potassium helps balance the amount of sodium in your cells. If you don't consume or retain enough potassium, you may accumulate too much sodium in your blood.
- Too little vitamin D in your diet. It's uncertain if having too little vitamin D in your diet can lead to high blood pressure. Researchers think vitamin D may affect an enzyme produced by your kidneys that affects your blood pressure. More studies are necessary to determine vitamin D's role in blood pressure.
- Drinking too much alcohol. Over time, heavy drinking can damage your heart. Having more than two or three drinks in a sitting can also temporarily raise your blood pressure, as it may cause your body to release hormones that increase your blood flow and heart rate.
- Stress. High levels of stress can lead to a temporary, but dramatic, increase in blood pressure. If you try to relax by eating more, using tobacco or drinking alcohol, you may only increase problems with high blood pressure.
- Certain chronic conditions. Certain chronic conditions also may increase your risk of high blood pressure, including high cholesterol, diabetes, kidney disease and sleep apnea.
The excessive pressure on your artery walls caused by high blood pressure can damage your blood vessels, as well as organs in your body. The higher your blood pressure and the longer it goes uncontrolled, the greater the damage.
Uncontrolled high blood pressure can lead to:
- Damage to your arteries. This can result in hardening and thickening of the arteries (atherosclerosis), which can lead to a heart attack, stroke or other complications.
- Aneurysm. Increased blood pressure can cause your blood vessels to weaken and bulge, forming an aneurysm. If an aneurysm ruptures, it can be life-threatening.
- Heart failure. To pump blood against the higher pressure in your vessels, your heart muscle thickens. Eventually, the thickened muscle may have a hard time pumping enough blood to meet your body's needs, which can lead to heart failure.
- A blocked or ruptured blood vessel in your brain. High blood pressure in the arteries leading to your brain can either slow the blood flow to your brain or cause a blood vessel in your brain to burst, causing a stroke.
- Weakened and narrowed blood vessels in your kidneys. This can prevent these organs from functioning normally.
- Thickened, narrowed or torn blood vessels in the eyes. This can result in vision loss.
- Metabolic syndrome. This syndrome is a cluster of disorders of your body's metabolism — including increased waist circumference, high triglycerides, low high-density lipoprotein (HDL), or "good," cholesterol, high blood pressure, and high insulin levels. If you have high blood pressure, you're more likely to have other components of metabolic syndrome. The more components you have, the greater your risk of developing diabetes, heart disease or stroke.
- Trouble with memory or understanding. Uncontrolled high blood pressure also may affect your ability to think, remember and learn. Trouble with memory or understanding concepts is more common in people who have high blood pressure.
Your risk of high blood pressure (hypertension) increases with age, but getting some exercise can make a big difference. And if your blood pressure is already high, exercise can help you control it. Don't think you've got to run a marathon or join a gym. Instead, start slow and work more physical activity into your daily routine.
How exercise can lower your blood pressure
How are high blood pressure and exercise connected? Regular physical activity makes your heart stronger. A stronger heart can pump more blood with less effort. If your heart can work less to pump, the force on your arteries decreases, lowering your blood pressure.
Becoming more active can lower your systolic blood pressure — the top number in a blood pressure reading — by an average of 5 to 10 millimeters of mercury (mm Hg). That's as good as some blood pressure medications. For some people, getting some exercise is enough to reduce the need for blood pressure medication.
If your blood pressure is at a desirable level — less than 120/80 mm Hg — exercise can keep it from rising as you age. Regular exercise also helps you maintain a healthy weight, another important way to control blood pressure.
But to keep your blood pressure low, you need to keep exercising. It takes about one to three months for regular exercise to have an impact on your blood pressure. The benefits last only as long as you continue to exercise.
How much exercise do you need?
Flexibility and strengthening exercises such as lifting weights are an important part of an overall fitness plan, but it takes aerobic activity to control high blood pressure. And you don't need to spend hours in the gym every day to benefit. Simply adding moderate physical activities to your daily routine will help.
Any physical activity that increases your heart and breathing rates is considered aerobic. Mowing the lawn, raking leaves or scrubbing the floor counts — as long as it takes effort. Other common forms of aerobic activity include climbing stairs, walking, jogging, bicycling and swimming.
Aim for at least 30 minutes of aerobic activity most days of the week. If you can't set aside that much time at once, remember that shorter bursts of activity count, too. Try taking the stairs instead of the elevator or taking a walk during your lunch break.
When you need your doctor's OK
Sometimes it's best to check with your doctor before you jump into an exercise program, especially if:
- You're a man older than age 40 or a woman older than age 50
- You smoke
- You're overweight or obese
- You have a chronic health condition, such as high blood pressure or high cholesterol
- You've had a heart attack
- You have a family history of heart-related problems before age 55
- You feel pain in your chest or become dizzy with exertion
- You're unsure if you're in good health
If you take any medication regularly, ask your doctor if exercising will make it work differently or change its side effects — or if your medication will affect the way your body reacts to exercise.
Keep it safe
To reduce the risk of injury while exercising, start slowly. Remember to warm up before you exercise and cool down afterward. Build up the intensity of your workouts gradually.
If you'd like to try strength training exercises, make sure you have your doctor's OK. Some of these exercises may increase your blood pressure — especially if you hold your breath while contracting your muscles.
Stop exercising and seek immediate medical care if you experience any warning signs during exercise, including:
- Chest pain or tightness
- Dizziness or faintness
- Pain in an arm or your jaw
- Severe shortness of breath
- An irregular heartbeat
- Excessive fatigue