High Blood Pressure (Hypertension)
Many people have high blood pressure (also called hypertension) without knowing it. That's why it's sometimes called “the silent killer.” If you don't detect and treat high blood pressure, it greatly increases your risk of heart attack and stroke.
What is blood pressure? Blood pressure is the force of blood pressing against the walls of the arteries, like the pressure of water in a garden hose.
What is high blood pressure and why is it bad for your heart? Sometimes blood pressure increases to help your body deliver more blood where it's needed-for instance, to your muscles during exercise. However, if the blood pressure stays high for prolonged periods of time, your heart has to pump blood against more resistance. This makes your heart, and your arteries, more prone to injury. Here's what can happen:
- Arteries can become scarred, hardened, and severely weakened
- Atherosclerosis (fatty plaque buildup in artery walls) can develop or increase
- Blood clots can form in the arteries
- The heart muscle can enlarge and weaken making it a less efficient pump
These changes to your arteries and heart reduce the amount of oxygen delivered to all your vital organs. This increases your risk for heart attacks, strokes, and other serious health problems.
Cholesterol is a soft, waxy substance that carries digested fat from your liver to parts of your body that need fat for energy and healing. It also carries fat to “fat storage sites” in your body such as your stomach and hips. Your liver produces most of the cholesterol in your body, but some comes from eating foods high in cholesterol and saturated fats.
Cholesterol and fat travel in your bloodstream in packages called lipoproteins. Lipoproteins are classified by their density, and different types play different roles in the health of your heart.
What are the different types of cholesterol and fat-and are they all bad? A certain amount of fat and cholesterol in your blood is healthy and normal. However, high cholesterol levels and fat in your blood or abnormal levels of certain types of these substances can cause atherosclerosis. All of the following increase your risk:
- High levels of LDL cholesterol (“bad cholesterol”). LDLs are low-density lipoproteins. These carry the largest amount of cholesterol in the blood. When too much LDL cholesterol circulates in your bloodstream - which can happen if you eat too much fat or cholesterol - it can build up in the walls of your arteries. Along with other substances, LDL cholesterol can form hard plaque in your arteries and cause atherosclerosis. This brings serious risks for your heart and other vital organs.
- Low levels of HDL cholesterol (“good cholesterol”). HDLs are high-density lipoproteins. Too little HDL cholesterol in your bloodstream can also increase your heart risk. That's because HDL cholesterol removes some of the LDL cholesterol from the artery walls, preventing or slowing the buildup of dangerous plaque. You want high levels of this “good” HDL to help keep your arteries clear and your heart protected.
- High levels of triglyceride. Triglyceride is the most common type of fat in your blood. Studies show that many people who have heart disease have high triglyceride levels. High triglyceride levels, combined with low HDL cholesterol or high LDL cholesterol, seem to speed up atherosclerosis.
How are cholesterol problems diagnosed? Your healthcare providers can check your blood cholesterol with a blood test called a lipid panel or lipid profile.
You already know that smoking damages your lungs and increases your chance of developing dangerous lung diseases. You might even have heard that smoking is bad for your skin and eyes. But did you know that smoking can also hurt your heart? Here's what it can do:
- Speed up atherosclerosis. Smoking damages the tissues of the artery walls, constricts blood vessels, and raises blood cholesterol. All of these can speed the buildup of fatty plaque in your arteries- and increase your risk for heart problems.
- Increase strain on your heart. When atherosclerosis narrows blood vessels, your heart has to work harder to pump blood throughout the body. Nicotine also causes your heart rate to increase and the blood vessels to constrict-both of which add to the strain on your heart.
- Lower the amount of oxygen in your blood. Because a smoker's heart muscle is working harder, it requires more oxygen. Yet smoking actually decreases the oxygen level in the blood. The carbon monoxide in cigarette smoke replaces as much as 15-20% of the oxygen normally carried by the red blood cells.
- Increase your risk of spasms and blood clots in your coronary arteries. Spasms and blood clots can cause heart attacks.
Diabetes and High Blood Glucose Levels
If you have diabetes, you're prone to having too much glucose (sugar) in your blood. This excess blood glucose can damage your blood vessels and increase your risk for heart attack, stroke, and other health problems. In fact, about 2/3 of people with diabetes die from a heart attack or stroke. Controlling your blood glucose levels can help prevent these and other complications.
Even if you don't have diabetes, your blood glucose levels may be higher than normal-a condition often called pre-diabetes. Studies show that regular exercise, a healthy diet, and reaching and maintaining a healthy weight can reduce blood glucose levels and delay or even prevent diabetes.
Physical inactivity is a major risk factor for coronary artery disease. Many studies have confirmed that people who don't get regular exercise are more likely to develop heart disease, and are more likely to die from a heart attack should one occur. People in this group are also more likely to have other cardiac risk factors such as high blood pressure, excess weight, and diabetes.
Experts agree that physical activity should be performed regularly. It doesn't matter if it's a structured program or part of your daily routine, all exercise adds up to a healthier heart. Even small increases in daily activity can reduce your risk of heart problems.
If you have a lot of excess weight from body fat, you're more likely to develop heart disease. This is true even if you have no other risk factors. Excess body fat hurts your heart in the following ways:
- Puts extra strain on your heart muscle
- Raises blood cholesterol and triglyceride levels, and lowers HDL
- Increases your risk of developing type 2 diabetes
- Raises blood pressure
How do you know if you need to lose weight? Healthcare providers use several different measures to assess body weight. Common ways of looking at body weight include the following:
- Body mass index (BMI). This is a measure of body fat based on your height and weight.
- Waist circumference and waist-hip ratio. Measuring your waist and hips can show where your body tends to store fat. People who store body fat around their waist tend to have a higher risk for heart disease.
- Body composition measures. Several different methods-for example, skin fold tests and underwater weighing-can determine how much of your weight is due to muscle or fat.