Can we reduce plaque buildup in arteries?

Cholesterol is a fatty substance that occurs naturally in the body. Cholesterol is often vilified as the bad guy, but we need this waxy, fatty substance to make vitamin D, hormones, bile that aids digestion, and the coverings of our cells. The liver produces 75% of the body's cholesterol, but all cells have the ability to make it.

When cells need more cholesterol, the liver sends it via the bloodstream in packages made of cholesterol on the inside and protein on the outside. These cholesterol-laden particles are known as low-density lipoprotein (LDL).

The problem occurs when there is too much LDL in the blood. High blood levels of cholesterol promote the formation and growth of plaques in your arteries, which put you at risk for heart attack and stroke. That's why LDL is known as "bad" cholesterol.

What causes arterial plaque?

Plaque forms when cholesterol lodges in an artery wall. To fight back, the body sends white blood cells to trap the cholesterol, which causes inflammation. That triggers cells in the artery wall to multiply and form a thin cap over the area.

But the soft plaque beneath the cap is dangerous. For example, a spike in blood pressure puts pressure on the cap. If it breaks, the body responds as it would to an injury: it forms a clot, which can block blood flow and cause a heart attack. Most major heart attacks occur when plaques rupture.

Plaques that gradually enlarge over time are often covered by thick, fibrous caps that can resist breaking apart. They can still block blood flow, causing angina (chest pain brought on by exertion or emotional stress). These blockages also can lead to different types of heart attacks.

Can you unclog your arteries or reduce plaque buildup?

Making plaques disappear is not possible, but with lifestyle changes and medication they can shrink and stabilize.

Doctors especially want to target the softer plaques before they rupture. For example, if you have a partial blockage in an artery from soft plaque, the goal is to try to reduce the cholesterol that's inside so the plaque shrinks, leaving nothing under the cap.

How do you get the cholesterol out of the plaque? By lowering levels of cholesterol in the blood, where it travels inside particles called lipoproteins that deposit cholesterol into blood vessel walls. Aggressive lowering of blood cholesterol (through statins, for example) can help stabilize plaque and in some cases shrink it.

The drugs used most often to reduce LDL cholesterol levels are statins - such as atorvastatin (Lipitor), simvastatin (Zocor), and rosuvastatin (Crestor). Statins block the liver enzyme that promotes cholesterol production. They also toughen the caps covering plaques, making them less vulnerable to rupture.

Very intensive lifestyle changes also have been shown to shrink plaques. Those lifestyle modifications include the following:

Eating a Mediterranean diet

Following a Mediterranean-style eating pattern can reduce heart disease risk by 30%. It's rich in olive oil, fruits, vegetables, beans, nuts, and seeds, with moderate amounts of fish, poultry, and dairy. Red meat and processed foods are minimized.

Kicking the habit

Smoking damages the lining of the arteries. Quitting can help raise high-density lipoprotein (HDL) levels. HDL - often referred to as "good" cholesterol - carries LDL cholesterol to the liver, where it's removed from the body.

Exercising

Aerobic exercise can raise HDL levels, lower blood pressure, burn body fat, and lower blood sugar levels. Exercise combined with weight loss also can lower LDL cholesterol levels. Aim for at least 150 minutes per week of moderate-intensity exercise (in which you breathe faster and your heart rate increases, but you can still carry on a conversation).

How much HDL and LDL should you aim for?

An HDL of 60 milligrams per deciliter (mg/dL) or higher is associated with a lower risk of heart disease. Your personal goal for LDL depends on your cardiovascular risk profile. For people who have coronary artery disease or other evidence of cardiovascular disease, the goal is an LDL of less than 70 mg/dL, and some health care providers are now aiming for an LDL of less than 55 mg/dL.

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