What Causes Heart Disease?

Updated on February 02, 2020

Heart disease develops when tissues of the cardiovascular system (heart or blood vessels) become damaged and dysfunctional. Damage to nearly any part of the heart or blood vessels can lead to damage in other parts. For instance, hypertension (high blood pressure) can cause atherosclerosis (fatty plaques that narrow the arteries), and atherosclerosis causes coronary artery disease, which causes potentially fatal heart attacks. In other words, one type of heart disease is a major risk factor for another type of heart disease.

Risk Factors for Heart Disease

While researchers have established that both hereditary and environmental factors influence a person’s risk for developing heart disease, no one is certain why some people get heart disease and some people don’t. Most scientists believe heart disease is most likely caused by a combination of inherited and environmental factors.

Risk for heart disease rises with age. Women are at greater risk for heart disease around age 55, after menopause. For men, the risk begins about 10 years earlier. In the U.S., the average age at first heart attack is about 65 for men and 72 for women. Between 4 and 10 percent of heart attacks strike people – mostly men – younger than 45.

Hereditary Factors

Heart disease is not directly passed on in a straightforward pattern, but having close family members with heart disease raises your risk for developing heart disease yourself. Your risk is higher if your father or brother was diagnosed with heart disease before age 55, or your mother or sister was diagnosed with heart disease before age 65. Most researchers believe that the risk for heart disease is influenced by many different genes.

Some people are born with congenital heart defects that increase their risk for developing serious heart disease later on.

Environmental and Behavioral Factors

The three most important factors that influence the development of heart disease are:

Smoking and inhaling second-hand smoke
Hypertension
High cholesterol

Other risk factors for heart disease include:

Type 2 diabetes
Being overweight or obese
More than two alcoholic drinks a day for men, or one drink for women
High levels of stress
Sedentary (inactive) lifestyle
Diet high in saturated (animal) fats, trans fats, cholesterol
Diet high in sodium for those with hypertension

Some types of heart disease are caused by a bacterial, viral, or fungal infection. In some cases, heart disease is a late side effect of radiation therapy for cancer.

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FAQ

Can heart disease be prevented?
Since we do not yet know what causes some people to develop heart disease, there is no certain way to prevent it. Some risk factors, including genetic predisposition and congenital heart defects, are beyond anyone’s control.

If you are concerned that you may have a high risk for developing heart disease, focus on lowering your risk by changing the factors within your control. Ways to lower the risk for developing heart disease include:

Stop smoking and avoid inhaling secondhand smoke.
Reduce your intake of alcohol.
Increase your activity level and try to get some daily exercise.
Work toward reaching and maintaining a healthy weight.
If you have hypertension, reduce your intake of sodium.
If you have type 2 diabetes, monitor and manage your blood glucose, to keep it at a healthy level.
Look for ways to limit the amount of stress in your life and learn new techniques to manage stress.
Focus your diet on fresh vegetables and fruit, whole grains, legumes such as beans and lentils, fish, low-fat dairy products, and sources of healthy unsaturated fats such as olive oil and nuts.

These changes may or may not help prevent heart disease, but they are likely to improve your overall health.

Do women have a lower risk for heart disease than men?
There is not an easy answer to this question. Cardiovascular disease is the most common cause of death among both men and women. In the past, women were thought to have a lower risk for heart disease than men. It is true that women generally develop heart disease later than men – women’s risk for heart disease begins to rise at age 55, compared with men at age 45.

Women are more likely than men to die in the year following a heart attack, and more likely to have a second heart attack within six years. Women actually have a higher risk for stroke than men, in part because they tend to live longer. Women are more likely to develop small vessel disease – blockages in the small blood vessels within the heart – as opposed to blockages in the larger coronary arteries typically seen in men. And women have a higher risk than men of developing takotsubo cardiomyopathy, also known as broken heart syndrome, in response to emotional distress.

There are a number of conditions only affecting women that significantly raise the risk for heart disease. Endometriosis and polycystic ovary syndrome (PCOS) both raise a woman’s risk of developing heart disease, as do gestational diabetes and high blood pressure during pregnancy.

Women may experience different heart disease symptoms from men, which may delay their diagnosis and treatment. It is safe to say that men and women have different risk factors for heart disease and may experience heart disease in different ways.