Some risk factors for heart disease are within your control, while others are not. The number of risk factors that affect you may change over the course of your lifetime. Having one or more of the major, proven risk factors doesn’t mean that you will develop cardiovascular disease or die of it. But generally, the more of these factors that apply to you, the more likely you are to develop the disease at some point. By knowing your own constellation of risk factors, you can control as many as possible and reduce your risk. These are the factors you can’t control:

•Gender. Men are more likely than women to have a heart attack at a younger age. Women are generally protected from heart disease by their sex hormones until menopause. Cardiovasculardisease is still the leading cause of death for women, however. After menopause, a woman’s risk of heart disease starts to rise. After the age of 65, a woman’s chance of having coronary artery disease is about the same as a man’s, and after 75, a woman is at even greater risk than a man is.
• Increasing age. Your risk of disease increases as you grow older.
More than 80 percent of people who die from heart disease are over 65. As you age, your heart’s function tends to weaken. The heart is less able to pump blood, the walls of the heart may thicken, and the walls of the arteries may stiffen and narrow. In addition to atherosclerosis, other conditions such as hypertension may compound the problem. Clearly this process is affected by lifestyle, including diet and exercise.
• Heredity. Cardiovascular disease runs in families, and you are more likely to develop it if your parents or siblings have coronary artery disease. Increased risk is linked to a family history of death from heart disease at a young age. Speci?cally, this is de?ned as coronary artery disease in men before age 55 and women before age 65. Your racial or ethnic background is another aspect of your heredity. In the United States, blacks are at higher risk than whites, in part because of higher rates of high blood pressure. The risk of heart disease is also somewhat higher in Mexican Americans and native Hawaiians. You can’t change your heredity, but it gives you strong motivation to manage other factors that you can change.
The major proven risk factors for heart disease that you can modify, control, or treat are:
• High blood cholesterol. High blood cholesterol directly increases your risk of heart disease. Cholesterol is a fatlike sub- stance that is carried in your blood, but excess cholesterol enters your body through foods derived from animals (meat, eggs, dairy products).
• High blood pressure (hypertension). High blood pressure increases your risk of several forms of cardiovascular disease: coro- nary artery disease, heart attack, kidney failure, congestive heart failure, and stroke. Other factors, such as obesity, alcohol abuse, unhealthy diet, or physical inactivity can contribute to high blood pressure, but you can also have it independent of those other in?u- ences. (See chapter 3.)

Obesity and overweight. Excess body fat contributes to the risk of heart dis- ease, independent of other risk factors, because it increases the heart’s work- load. It also raises blood pressure, adversely affects cholesterol levels, and contributes to the development of dia- betes.
• Physical inactivity. An inactive lifestyle increases the risk of becoming overweight and developing high blood cholesterol levels, high blood pressure, and diabetes. Even moderate amounts of regular exercise will lower your risk of heart disease.
• Type 2 diabetes. Having diabetes puts you at serious risk; about 65 to 75 per- cent of people with diabetes die from some form of cardiovascular disease. Controlling your diabetes may help control your risk of heart problems.
• Smoking. If you smoke, you are more likely to develop cardiovascular disease than a nonsmoker is—in addition to the

Heart Disease and Genetics

Because heart disease tends to run in fami- lies, having parents or siblings with the dis- ease is a major risk factor. But there is no single gene for cardiovascular disease; in fact, geneticists think that more than a thousand separate genes may influence the overall cardiovascular system. There are separate genes for obesity, high blood pressure, and diabetes, all risk factors for heart disease. Scientists are still identifying these genes and studying how they interact with one another—and with other influences such as diet—in an individual or a family. Many geneticists believe that one of the most effec- tive approaches for a person at high genetic risk of heart disease is to ensure that the per- son follows a healthy lifestyle.
Other avenues of research include devel- oping drugs that target a specific genetic pre- disposition, along with developing genetic tests that can screen for high-risk patients. The ultimate implications of genetic research for testing and treatment of heart disease are still far in the future.

risk of lung cancer. Smoking increases your heart rate, constricts your arteries and contributes to their obstruction with plaque, and can cause irregular heartbeat. It also increases your risk of blood clots, which cause heart attack or stroke. Even exposure to other people’s smoke increases a person’s risk of heart disease.
• Early menopause. Women who have early menopause, whether naturally or as a result of surgery, have a higher risk of coronary artery disease.
Other in?uences, called contributing factors, are linked to heart dis- ease, but their signi?cance is not fully understood or measured yet. These factors are:
• Stress. Stress, particularly in some people, appears to increase the risk of heart problems, perhaps because it raises your heart rate and blood pressure, damaging your arteries over time. It may also

contribute to other harmful behaviors such as overeating, smok- ing, or drinking too much.
• Alcohol. Drinking more than a moderate amount of alcohol can raise blood pressure, negatively affect cholesterol and triglyceride (blood fats) levels, and cause irregular heartbeats. However, mod- est amounts of alcohol may actually reduce the risk of heart dis- ease. Since so many Americans drink to excess, doctors are reluctant to recommend moderate drinking to improve heart health, for fear that “moderate” usage will change to “excessive” use. Alcohol, whether wine, beer, or liquor, but only in moderate amounts, may be helpful to your health.
• Birth control pills. If you smoke or have high blood pressure, and especially if you are over 35, birth control pills may increase your risk of heart disease. Today’s birth control pills contain much lower levels of hormones than early ones and are generally consid- ered safe, independent of other risk factors. You should not smoke and take birth control pills, especially over age 35, due to the increased risk of heart attack and blood clots.