Your blood moves through tubes. 
Your blood moves through tubes. 

Your body uses tubes called arteries to carry blood. These tubes bring oxygen to your organs. Sometimes, a buildup happens inside the artery walls. This buildup is called plaque. 
This buildup happens very slowly. It can even start when you are young. Most people do not feel sick at first. The arteries may get thicker, but the blood still flows. But as plaque grows, the tubes get narrow. This makes it hard for blood to move. 
If the blood cannot reach an organ, it causes problems. Narrow tubes in the heart can cause chest pain. Narrow tubes in the brain can cause a stroke. A stroke happens when brain cells die from lack of blood. Many things can increase your risk. These include smoking, high blood pressure, and diet. You can help by eating healthy food and exercising. Doctors can also use medicine to help.
Atherosclerosis is a long-term disease that affects the walls of your arteries. 
The way this works is a slow, step-by-step process. It often starts when low-density lipoprotein (LDL) particles enter the artery wall. LDL is a type of cholesterol found in your blood. Once inside, these particles become oxidized. This triggers an inflammatory response, which is how the body reacts to damage. 
Scientists have studied this for a long time. The disease was first described back in 1575. However, it may be part of our very history. Some evidence suggests it comes from genetic mutations. These mutations may have happened over two million years ago. They likely occurred in the ancestors of modern humans. 
There are many important facts about how this affects people. Most people are affected by this by age 65. It is the top cause of death and disability in developed countries. In one study of 300 soldiers from the Korean War, 77.3 percent had signs of the disease. The average age of those men was only 22.1 years.
You can think of your arteries like water pipes in a house. If gunk builds up inside the pipes, the water cannot flow well. If a pipe gets blocked, the sink might stop working. In the body, if the heart's pipes narrow, you might feel chest pain. If the pipes to the brain narrow, it can cause a stroke. 
Atherosclerosis is a chronic inflammatory disease that affects the walls of the arteries.
The process of plaque buildup is called atherogenesis. It is a slow process that develops over many years. It begins when low-density lipoprotein (LDL) particles enter the endothelium. The endothelium is the thin lining on the inside of the artery. Once inside the wall, these LDL particles become oxidized through biochemical reactions. This oxidation triggers an inflammatory response in the vessel. 
These macrophages attempt to clean up the area by ingesting the oxidized cholesterol. However, this process leads to the formation of a complex plaque. This plaque is composed of fat, cholesterol, immune cells, and calcium. 
Symptoms of atherosclerosis often do not appear for many decades. This is because the arteries can enlarge at plaque locations to maintain blood flow. Most people only realize they have the disease when a major event occurs. For example, a sudden rupture of a plaque can lead to a blood clot. This clot can cause a total blockage of the artery.
The impact of this disease is widespread and significant. It is the leading cause of death and disability in developed countries. Most people are affected by some degree of atherosclerosis by the age of 65. Historical studies have shown how early this process can begin. In an autopsy of 300 U.S. soldiers from the Korean War, 77.3 percent showed evidence of coronary arteriosclerosis. The average age of these men was only 22.1 years. 
Different locations in the body produce different medical outcomes. If the coronary arteries narrow, a person may experience angina, which is chest pain. They might also feel shortness of breath, nausea, or palpitations. 
Scientists are still working to understand the exact causes of this disease. It is believed to be multifactorial, meaning many different things contribute to it. Risk factors include high blood pressure, diabetes, and obesity. Smoking and an unhealthy diet are also major contributors. Some people also have a genetic predisposition that makes them more likely to develop the disease. 
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