Oxidized cholesterol is the oxidation of low-density lipoprotein (LDL) cholesterol, which can build up as plaque in the walls of the arteries.

Oxidization is a chemical process that occurs in the body. Oxidized cholesterol occurs when this chemical reaction affects LDL cholesterol.

Excess oxidized cholesterol can build up in the walls of the arteries, which can be dangerous and can contribute to health conditions such as heart disease and stroke.

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Free radicals, which are unstable molecules, oxidize LDL cholesterol. An imbalance between free radicals and antioxidants in the body can lead to oxidative stress, which damages lipids, proteins, and other substances in the body.

Certain factors can increase free radicals in the body, including:

  • environmental pollutants
  • radiation
  • ultraviolet (UV) exposure
  • smoking
  • certain chemical compounds, such as xanthine oxidase

LDL is susceptible to oxidation. Eating an unbalanced diet, not getting enough exercise, and smoking can all increase oxidative stress and oxidized LDL in the body.

Oxidation and inflammation also increase the risk of plaques coming loose. If plaque breaks away, it can cause a blood clot and blockage within blood vessels.

According to a 2020 article, oxidized LDL is one of the most important risk factors in atherosclerosis.

Atherosclerosis is a narrowing of the arteries due to plaque buildup on the arterial walls. Cholesterol, fat, and certain substances in blood all contribute to plaque formation.

According to the article, oxidized LDL can build up in the inner lining of blood vessels, which can cause inflammation and the development of atherosclerosis.

Within the blood vessels, oxidized LDL can stimulate an immune response and cause inflammation in the body.

Atherosclerosis reduces blood supply through the body and can lead to severe complications, including:

Oxidized cholesterol can contribute to atherosclerosis, which may not produce symptoms in the early stages. If the disease progresses, it may cause the following conditions and symptoms:

Condition or effectCommon symptoms
coronary heart disease• chest pain
• shortness of breath
• dizziness
• fatigue
peripheral artery disease• painful, aching, or cramping legs
• symptoms that ease with rest
vertebral artery disease• memory and thinking problems
• vision problems
• numbness or weakness on one side of the face or body
reduced blood flow to the intestines• pain after eating
• diarrhea
• unexplained weight loss

In males, erectile dysfunction can also be an early warning sign of plaque buildup in the arteries.

Doctors may use an enzyme-linked immunosorbent assay (ELISA) to check for levels of oxidized LDL in the blood. They will take a blood sample and send it to a laboratory for testing.

ELISA is a technique for measuring certain antibodies, proteins, and other substances in a sample of bodily fluid.

People may also be able to order an oxidized LDL test online. They will need to visit a local laboratory to undergo the test and wait to receive their results online. People may then want to discuss their results with a doctor.

High-density lipoprotein (HDL) cholesterol helps reduce oxidation and inflammation and prevent plaque formation in the arteries. Increasing HDL cholesterol levels and lowering LDL levels may help reduce oxidized cholesterol.

Increasing antioxidants in the diet may also help reduce oxidized LDL and counter its adverse effect on the arteries.

High fat diets can contribute to high cholesterol levels as well as increase oxidative stress and inflammation. Dietary factors that may help reduce oxidized cholesterol include:

  • reducing intake of unhealthy fats, such as trans and saturated fats
  • moderating calorie intake
  • reducing intake of simple sugars, such as refined carbohydrates
  • maintaining a moderate weight

Diets high in polyphenols and low in simple sugars, such as the Mediterranean diet, may help reduce oxidized LDL.

Eating a diet high in polyphenols may help prevent oxidized LDL and reduce the risk of health conditions such as obesity and high blood pressure.

Polyphenols are compounds in plants with strong antioxidant effects. This antioxidant activity can help target excess oxidation in the body. People can include polyphenols in their diet by eating plenty of fruits, vegetables, nuts, and legumes.

Reducing or avoiding trans and saturated fats may also help prevent oxidized LDL.

Maintaining a healthy lifestyle may help prevent certain factors that can damage the lining of the blood vessels, which allows the penetration of LDL in the bloodstream. These factors include:

Ways to help prevent high cholesterol include:

If people wish to check their cholesterol levels, including oxidized cholesterol, they can talk with their doctor. People may also want to discuss risk factors for atherosclerosis.

If a person has any symptoms of plaque buildup or atherosclerosis, they should contact a doctor. This can include symptoms relating to reduced blood flow in the body, such as:

  • shortness of breath
  • dizziness
  • cognitive changes

People can discuss a treatment plan with a doctor. Diet and lifestyle factors, and sometimes medication, can help prevent or slow down the buildup of plaque in the arteries.

Oxidized cholesterol occurs due to a chemical reaction with LDL cholesterol. This can lead to an increase in inflammation and plaque buildup in the walls of the arteries.

Excessive oxidized cholesterol may lead to atherosclerosis and increase the risk of cardiovascular disease, among other health issues.

Maintaining healthy cholesterol levels and eating a diet high in antioxidants and low in trans or saturated fats and sugars may help reduce or prevent oxidized cholesterol.