What Causes Heart Disease?

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 percent 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 secondhand smoke
• Hypertension
• High cholesterol

Other risk factors for heart disease include:

• 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.

Can Heart Disease Be Prevented?

Since it is not clear 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 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.

Condition Guide

• Heart Disease – An Overview
• Heart Disease – The Path to Diagnosis
• Symptoms of Heart Disease
• Treatments for Heart Disease
• Types of Heart Disease