Apolipoprotein A1

What is Apolipoprotein A1?

Apolipoprotein A-I (ApoA1) is the primary structural protein of HDL particles. It activates the enzyme LCAT, which is essential for reverse cholesterol transport — the process of removing cholesterol from arterial walls back to the liver. ApoA1 also has direct anti-inflammatory and antioxidant effects on blood vessels.

What might a high or low Apolipoprotein A1 mean?

Low ApoA1 indicates reduced HDL particle count and impaired reverse cholesterol transport. The ApoB/ApoA1 ratio is one of the strongest predictors of cardiovascular risk — a high ratio means more atherogenic particles relative to protective ones. ApoA1 reflects HDL particle number more accurately than HDL-C reflects HDL function.

What is the typical reference range for Apolipoprotein A1?

The general-population reference range shown here is 104 – 202 mg/dL. Reference ranges describe the general population and are not a personal target — discuss your results with your physician.

What can affect Apolipoprotein A1?

It may be higher with: Aerobic exercise, Moderate alcohol consumption, Weight loss, Omega-3 fatty acids, Smoking cessation, Niacin. It may be lower with: Smoking, Sedentary lifestyle, Obesity, Anabolic steroids, Very low-fat diets, Uncontrolled diabetes.