ORAC stands for Oxygen Radical Absorbance Capacity.
Oxygen radicals are a normal everyday part of living.
They are in our bodies all the time. But, even though we have these oxygen radicals, they can be bad for us - they can damage our cells. If our bodies have weapons to absorb these oxygen radicals, then they won't hurt us. Oxidation is a natural process that occurs around us all the time. One example of oxidation is rusting.