Brunswick Labs - Developer of ORAC Test

 

Does the improved ORAC assay measure the total antioxidant activity against all the radicals?
No. The improved ORAC assay only measures the antioxidant activity against peroxyl radical and hydroxyl radical. We are in the process to expand the ORAC method to other harmful species.
 

What does the ORAC value tell us?
The ORAC assays are performed in vitro, in the test tube, and therefore do not determine the bioavailability within the body. The high ORAC value indicates that the tested sample possesses a high potency of antioxidant activity chemically.


Can I use the published ORAC data for comparison purpose?
No. In the middle of the 90's, Cao and coworkers published the ORAC values of some vegetables and fruits1. The results primarily demonstrate that the ORAC assay is a valuable tool to evaluate the antioxidant activity. However, due to the limited sample sizes and varieties, the published ORAC values of vegetables and fruits are not comprehensive. Importantly, the most published ORAC results are obtained using the old method; therefore they are not valid anymore.  Furthermore, the naturally occurring antioxidants actually are the secondary metabolites of natural products; Mother Nature has a profound influence on their biosynthesis pathways.  For instance, the geographic locations, weather conditions and the varieties of the species have been determined to influence the antioxidant property chemically and physiologically. We screened over 1000 vegetables last year; the conclusion is that "not every broccoli is created equally"

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    Excerpt from Nutraceuticals World Article - March 2004

     

    Supplement products have been competing against each other for the title of “Highest ORAC Value.” However, with competitive use of ORAC values comes misconceptions and misuse. Are all these references to ORAC values comparable to each other? The translation to consumer vocabulary can be quite confusing. The ORAC value of foods is often reported per 100 grams, while ORAC value for supplements is reported per gram and often the units are completely left out. Many companies are comparing ORAC values of their products to equal antioxidant activity of servings of fruits and vegetables, but which fruits or vegetables and what is the serving size? For example, one company’s website claimed its product contained equal antioxidant activity as compared to 10 servings of fruits and vegetables, then further defines the equivalence by listing a head of lettuce and other low ORAC vegetables as part of the 10 servings.

     

    http://www.nutraceuticalsworld.com/March042.htm

     

    Excerpts from New Spirit:

     

    We now know that the total antioxidant capacity of food is far greater than the sum of these individual components. Certain fruits and vegetables contain a complex assortment of countless antioxidants that interact and potentate each other, pushing their "Antioxidant Powers" far above their mere additive value...
     

    Also surprising, it is not always fresh foods that have the greatest "antioxidant power." For example, the new ORAC test shows that a fresh plum has an ORAC value of 9.49 (per gram), compared to a dried plum (prune) with an ORAC value of 57.7 (per gram). 9 Another surprising example is the antioxidant power of grapes. Fresh grapes have an ORAC value of 4.46 (per gram) versus dried grapes (raisins) which have an ORAC value of 28.3 (per gram). 10 Why? Drying removes the water and concentrates their antioxidants.

    Does this mean we are only to eat dried foods?
    Of course this is not true. We consume foods not only for their antioxidant value, but for their nutritive value as well, which makes our bodies function properly. At the same time, we must not ignore the other values of food such as its "free radical absorbency capacity" or "antioxidant power". Most of us do not want to just feel good for the moment, we want the moment to last. We are all interested in anti-aging, like extension and quality of life. By learning of a foods ORAC value we may be one step closer to the "fountain of youth".
     

    http://www.newspirit.com/literature/techbulletins_orac.asp

     

    Excerpts from Cancer Decisions Report on Xango by Ralph Moss

     

    The main XanGo website also claims that the antioxidant ORAC (oxygen radical absorbance capacity) value of mangosteen is the highest of all edible plants. "It is so potent that literally I know of nothing else in the supplement market that can possibly come even close to it," says J. Frederic Templeman, MD, a Georgia family practitioner who is interviewed at the MyXanGo website. Many other XanGo-promoting websites repeat the claim that while the previous champion, prunes, have an ORAC value of 7,000 per ounce, mangosteen has an ORAC value of 17,000 to 24,000.  Yet XanGo sites claim that "a new champion" has been born in the worldwide contest for ORAC supremacy. But where in the scientific literature is the ORAC value of XanGo published? The source of these numbers is hard to track down.

     

    However, even if we assume for the sake of argument that the figures cited are indeed accurate, it must be pointed out that merely having an astronomically high ORAC value does not in and of itself confer any particular advantage. Not all antioxidants that are confirmed as present in the laboratory can be absorbed by human beings. And there is a limit to how much we can benefit from an increased intake of antioxidants.

     

    According to Dr. Ronald Prior of the US Department of Agriculture Research Service at Tufts University, Boston, Massachusetts, "a significant increase in antioxidants of 15 to 20 percent is possible by increasing consumption of fruits and vegetables, particularly those high in ORAC value." However, in order to have a significant impact on plasma and tissue antioxidant capacity one can only meaningfully increase one's daily intake by 3,000 to 5,000 ORAC units. Any greater amount is probably redundant. That is because the antioxidant capacity of the blood is tightly regulated, says Dr. Prior. Thus there is an upper limit to the benefit that can be derived from antioxidants. Taking in 25,000 ORAC units at one time (as reputedly occurs with mangosteen) would be no more beneficial than taking in a fifth of that amount: the excess is simply excreted by the kidneys.

     

    Although I myself have written a book on the subject of the benefit of antioxidants (Antioxidants Against Cancer), I would say it is a tremendous stretch to claim that antioxidants are predictably going to save anyone's life. Good health is achieved through a combination of many factors, hereditary as well as environmental.

    http://www.cancerdecisions.com/050904_page.html