Heart Disease Risk Factors

High Blood Cholesterol and High Triglyceride Levels

Cholesterol

High blood cholesterol is a condition in which there's too much cholesterol—a waxy, fat-like substance—in your blood. The higher your blood cholesterol level, the greater your risk for heart disease and heart attack.

Cholesterol travels in the bloodstream in small packages called lipoproteins (LI-po-pro-teens). Two major kinds of lipoproteins carry cholesterol throughout your body:

• Low-density lipoproteins (LDL). LDL cholesterol is sometimes called "bad" cholesterol. This is because it carries cholesterol to tissues, including your heart arteries. The higher the level of LDL cholesterol in your blood, the greater your risk for heart disease.
• High-density lipoproteins (HDL). HDL cholesterol is sometimes called "good" cholesterol. This is because it helps remove cholesterol from your arteries. A low HDL cholesterol level raises your risk for heart disease.

A number of factors affect your blood cholesterol levels. For example, after menopause, women's LDL cholesterol levels tend to rise and their HDL cholesterol levels tends to fall. Other factors, such as age, gender, and diet, also affect your cholesterol levels.

Healthy levels of both LDL and HDL cholesterol will prevent plaque from building up in your arteries. Routine blood tests can show whether your blood cholesterol levels are healthy. Talk to your doctor about having your cholesterol tested and what the results mean.

Children also can have high blood cholesterol, especially if they're overweight. Talk to your child's doctor about testing your child' cholesterol levels.

To learn more about high blood cholesterol and how to manage the condition, see the Diseases and Conditions Index (DCI) High Blood Cholesterol article and the National Heart, Lung, and Blood Institute's (NHLBI's) "Your Guide to Lowering Your Cholesterol With TLC."

Triglycerides

Triglycerides are another type of fat found in the blood. Some studies suggest that a high level of triglycerides in the blood also may raise the risk for heart disease, particularly in women.

High Blood Pressure

"Blood pressure" is the force of blood pushing against the walls of your arteries as your heart pumps out blood. If this pressure rises and stays high over time, it can damage your heart and lead to plaque buildup.

Often, high blood pressure (HBP) has no signs or symptoms. However, the condition can be detected using a simple test that involves placing a blood pressure cuff around your arm.

Most adults should have their blood pressure checked at least once a year. Talk to your doctor about how often you should have your blood pressure checked. If you have HBP, you will likely need to have your blood pressure checked more often.

Children also can develop HBP, especially if they're overweight. Your child's doctor should check your child's blood pressure at each routine checkup.

Blood pressure numbers consist of systolic (sis-TOL-ik) and diastolic (di-a-STOL-ik) pressures. Systolic blood pressure is the pressure when your heart beats. Diastolic blood pressure is the pressure when your heart is at rest between beats.

You will most often see blood pressure numbers written with the systolic number above or before the diastolic number, such as 120/80 mmHg. (The mmHg is millimeters of mercury—the units used to measure blood pressure.)

All levels above 120/80 mmHg raise your risk for heart disease. This risk grows as blood pressure levels rise. Only one of the two blood pressure numbers has to be above normal to put you at greater risk for heart disease and heart attack.

Blood pressure normally rises with age and body size. Newborns often have very low blood pressure numbers, while older teens have numbers similar to adults.

The ranges for normal blood pressure and HBP are generally lower for youth than for adults. These ranges are based on the average blood pressure numbers for age, gender, and height.

Your child should have routine blood pressure checks starting at 3 years of age. To find out whether a child has HBP, a doctor will compare the child's blood pressure numbers to average numbers for his or her age, height, and gender.

Both children and adults are more likely to develop HBP if they're overweight or have diabetes.

For more information about HBP and how to manage the condition, see the DCI High Blood Pressure article and the NHLBI's "Your Guide to Lowering Your Blood Pressure With DASH."

Diabetes and Prediabetes

Diabetes is a disease in which the body's blood sugar level is too high. The two types of diabetes are type 1 and type 2.

In type 1 diabetes, the body's blood sugar level is high because the body doesn't make enough insulin. Insulin is a hormone that helps move blood sugar into cells, where it's used for fuel. In type 2 diabetes, the body's blood sugar level is high mainly because the body doesn't use its insulin properly.

Over time, a high blood sugar level can lead to increased plaque buildup in your arteries. Having diabetes doubles your risk for heart disease.

Prediabetes is a condition in which your blood sugar level is higher than normal, but not as high as it is in diabetes. If you have prediabetes and don't take steps to manage it, you're likely to develop type 2 diabetes within 10 years. You're also at higher risk for heart disease.

Being overweight or obese raises your risk for type 2 diabetes. With modest weight loss and moderate physical activity, people who have prediabetes may be able to delay or prevent type 2 diabetes. They also may be able to lower their risk for heart disease and heart attack. Weight loss and physical activity also can help control diabetes.

Even children can develop type 2 diabetes. Most children who have type 2 diabetes are overweight.

Type 2 diabetes develops over time and sometimes has no symptoms. Go to your doctor or local clinic to have your blood sugar levels tested regularly to check for diabetes and prediabetes.

For more information on diabetes and prediabetes, see the National Institute of Diabetes and Digestive and Kidney Diseases' (NIDDK's) Introduction to Diabetes.

Overweight and Obesity

The terms "overweight" and "obesity" refer to a person's overall body weight and whether it's too high. Overweight is having extra body weight from muscle, bone, fat, and/or water. Obesity is having a high amount of extra body fat.

The most commonly used measure of overweight and obesity is body mass index (BMI). BMI is calculated from your height and weight.

In adults, a BMI of 18.5 to 24.0 is considered normal. A BMI of 25 to 29.9 is considered overweight. A BMI of 30 or above is considered obese. Over two-thirds of American adults are overweight, and almost one-third are obese. You can use the NHLBI's online BMI calculator to figure out your BMI, or your doctor can help you.

Overweight is defined differently for children and teens than it is for adults. Children are still growing, and boys and girls mature at different rates. Thus, BMIs for children and teens compare their heights and weights against growth charts that take age and gender into account. This is called BMI-for-age percentile.

For more information about BMI-for-age growth charts for children, go to the Centers for Disease Control and Prevention's BMI-for-age calculator.

Being overweight or obese can raise your risk for heart disease and heart attack. This is mainly because overweight and obesity are linked to other heart disease risk factors, such as high blood cholesterol and triglyceride levels, high blood pressure, and diabetes.

For more information, see the DCI Overweight and Obesity article.

Smoking

Smoking tobacco or long-term exposure to secondhand smoke raises your risk for heart disease and heart attack.

Smoking triggers a buildup of plaque in your arteries. Smoking also increases the risk of blood clots forming in your arteries. Blood clots can block plaque-narrowed arteries and cause a heart attack.

Some research shows that smoking raises your risk for heart disease in part by lowering HDL cholesterol levels.

The more you smoke, the greater your risk for heart attack. Studies show that if you quit smoking, you cut your risk for heart attack in half within a year. The benefits of quitting smoking occur no matter how long or how much you've smoked.

Most people who smoke start when they're teens. Parents can help prevent their children from smoking by not smoking themselves. Talk to your child about the health dangers of smoking and ways to overcome peer pressure to smoke.

Lack of Physical Activity

Inactive people are nearly twice as likely to develop heart disease as those who are active. A lack of physical activity can worsen other heart disease risk factors, such as high blood cholesterol and high triglyceride levels, high blood pressure, diabetes and prediabetes, and overweight and obesity.

It's important for children and adults to make physical activity part of their daily routines. One reason many Americans aren't active enough is because of hours spent in front of TVs and computers doing work, schoolwork, and leisure activities.

Some experts advise that children and youth reduce screen time because it limits time for physical activity. They recommend that children aged 2 and older should spend no more than 2 hours a day watching television or using a computer (except for school work).

Being physically active is one of the most important things you can do to keep your heart healthy. The good news is that even modest amounts of physical activity are good for your health. The more active you are, the more you will benefit.

For more information, see the U.S. Department of Health and Human Services' "2008 Physical Activity Guidelines for Americans," the Diseases and Conditions Index Physical Activity and Your Heart article, and the NHLBI's "Your Guide to Physical Activity and Your Heart."

Unhealthy Diet

An unhealthy diet can raise your risk for heart disease. For example, foods that are high in saturated and trans fats and cholesterol raise LDL cholesterol. Thus, you should try to limit these foods.

Saturated fats are found in some meats, dairy products, chocolate, baked goods, and deep-fried and processed foods. Trans fats are found in some fried and processed foods. Cholesterol is found in eggs, many meats, dairy products, commercial baked goods, and certain types of shellfish.

It's also important to limit foods that are high in sodium (salt) and added sugars. A high-salt diet can raise your risk for high blood pressure.

Added sugars will give you extra calories without nutrients like vitamins and minerals. This can cause you to gain weight, which raises your risk for heart disease. Added sugars are found in many desserts, canned fruits packed in syrup, fruit drinks, and nondiet sodas.

You also should try to limit how much alcohol you drink. Too much alcohol will raise your blood pressure. It also will add calories, which can cause weight gain.

Stress

Stress and anxiety may contribute to the development of heart disease. Stress and anxiety also can trigger your arteries to tighten. This can raise your blood pressure and your risk for heart attack.

The most commonly reported trigger for a heart attack is an emotionally upsetting event, especially one involving anger. Stress also may indirectly raise your risk for heart disease if it makes you more likely to smoke or overeat foods high in fat and sugar.

Age

As you get older, your risk for heart disease and heart attack rises. This is in part due to the slow buildup of plaque inside your heart arteries, which can start during childhood.

In men, the risk for heart disease increases after age 45. In women, the risk increases after age 55.

Most people have some plaque buildup in their heart arteries by the time they're in their seventies. However, only about 25 percent of those people have chest pain, heart attacks, or other signs of heart disease.

Gender

Before age 55, women have a lower risk for heart disease than men. After age 55, however, the risk for heart disease increases similarly in both women and men. This is because before menopause, estrogen provides some protection against heart disease for women.

Some risk factors may affect heart disease risk differently in women than in men. For example, diabetes raises the risk for heart disease more in women.

Family History

Family history plays a role in heart disease risk. Your risk increases if your father or brother was diagnosed with heart disease before 55 years of age, or if your mother or sister was diagnosed with the disease before 65 years of age.

However, having a family history of heart disease doesn't mean that you will have it too. This is especially true if your affected family member smoked or had other heart disease risk factors that were not well treated.

Making lifestyle changes and taking medicines to treat other risk factors often can lessen genetic influences and stop or slow the progress of heart disease.