Showing posts with label free radicals. Show all posts
Showing posts with label free radicals. Show all posts

Saturday, January 9, 2010

What is ORAC?

Free radicals have an important role in large number of biological processes, some of which are necessary for life, such as the intracellular killing of bacteria by phagocytic cells such as granulocytes and macrophages. Free radicals have also been implicated in certain cell signaling processes. Many diseases have their origin in inadequate free radicals activity in the body.



Many forms of cancer are thought to be the result of reactions between free radicals and DNA, resulting in mutations that can adversely affect the cell cycle and potentially lead to malignancy. Some of the symptoms of aging such as atherosclerosis are also attributed to free-radical induced oxidation of many of the chemicals making up the body. In addition free radicals contribute to alcohol-induced liver damage, perhaps more than alcohol itself. Radicals in cigarette smoke have been implicated in inactivation of alpha 1-antitrypsin in the lung. This process promotes the development of emphysema.


Knowing this, there was developed a method of measuring antioxidant capacities in biological samples. The method is called ORAC – an acronym for Oxygen Radical Absorbance Capacity. It has been discovered that a small group of super foods have up to twenty times the antioxidant power of other foods. This is why everybody recommends us to eat vegetables and fruits. It is recommended that we eat foods containing at least 3,000 ORAC units a day.

Here is a table containing some foods and their ORAC score.