Total Antioxidant Capacity of Plasma (measured as ORAC - Oxygen Radical Absorbance Capacity)

What Does This Test Measure?

The test evaluates the total antioxidant capacity of plasma, which combines multiple antioxidants present in your blood. These include vitamins (like vitamin C and E), enzymes, and other compounds that neutralize harmful free radicals. The ORAC method quantifies the overall ability of these antioxidants to absorb oxygen radicals, reflecting your body’s natural oxidative stress resistance.

Why Might You Need This Test?

This test may be ordered to evaluate overall oxidative health, especially if you have conditions linked to oxidative stress (e.g., chronic inflammation, certain cancers, or metabolic disorders). It can also help assess antioxidant supplementation effectiveness or monitor long-term exposure to oxidative damage.

How Is This Test Performed?

A blood sample is drawn from a vein, typically in your arm. The plasma portion is separated and analyzed using the ORAC assay, which measures its ability to neutralize free radicals over time.

What Does a Low or High Result Mean?

Results reflect the combined strength of your blood’s antioxidants. A lower capacity may indicate higher oxidative stress, while a higher capacity suggests stronger natural defenses. Interpretation depends on clinical context and your overall health.