Atherosclerosis, a disease that affects the large vessels of the body and typically progresses over time, is one of the major causes of heart attack and stroke. It begins with the development of fatty streaks in the blood vessels, which can start forming as early as childhood. Compounds that cause inflammation (including cholesterol and fat) infiltrate the inner layers of the arteries and lead to the development of these fatty streaks.

A cascade then starts in which the body produces cells that cause more inflammation. Over time—sometimes decades—this inflammatory cascade leads to a deposit of plaque on the blood vessel wall.

Atherosclerosis typically forms in large vessels. Blood clots, called thrombi, can happen when the plaque on the vessel walls breaks open. It can then block the blood flow to the heart, brain or legs. The obstruction of blood flow to the heart or brain is what causes heart attack or stroke in people with atherosclerosis.

A combination of risk factors that may be caused by genetic or environmental factors can lead to atherosclerosis. A few of these major risk factors include:

• High levels of low-density lipoproteins (LDL)
• Low levels of high-density lipoproteins (HDL)
• High blood pressure
• Family history
• Diabetes
• Cigarette smoking
• Lack of exercise

HDL and LDL make up the body’s total cholesterol. Cholesterol is made by the liver but may also be found in a variety of foods, including meat and full-fat dairy products. Not all cholesterol is bad—we need some of it so our bodies can perform a variety of physiological functions. But high levels of LDL flowing through the body may put us at a higher risk for atherosclerosis. On the other hand, HDL—often called “good” cholesterol—can lower our risk for atherosclerosis by absorbing circulating cholesterol and shuttling it back to the liver.

So, what can we do about atherosclerosis? While some of the risk factors are out of our hands, there are several things we can control. Maintaining a heart-healthy lifestyle, including 150 minutes of moderate-intensity or 75 minutes of vigorous exercise each week and a low-fat, produce-rich diet, will help control risk factors such as high blood pressure and imbalances of cholesterol levels.

Adopting healthy habits early is the key to reducing the risk of atherosclerosis. Because development of plaque is often decades in the making, it’s important to follow healthy behaviors way before signs of the disease are detected.