ORAC -- oxygen radical absorbance capacity -- is a standard that measures the antioxidant capacity of a food. Though the precise relationship between ORAC value and antioxidant activity in humans has not been established, foods with high ORAC value are thought to confer greater protective antioxidant effects and possibly reduce disease and extend lifespan, according to the United States Department of Agriculture. Research on antioxidant effects of foods with high ORAC values has shown some distinct health-promoting benefits.
Prunes and Raisins
Prunes have an ORAC value of 5,770 per 100 g -- about 3.5 oz. -- and raisins calculate to about half that value, putting these fruits high atop the list of ORAC values for fruits and vegetables. The low water content of prunes and raisins concentrates their nutrients, which may effectively raise their per-gram ORAC values and also, as a caution, their sugar content. A study on the antioxidant capacity of common beverages listed prune juice second behind coffee and ahead of green tea. Other beverages tested in the study included cocoa, grape juice and jasmine, black and oolong teas. The study was published in the February 2009 issue of the journal "Archives of Pharmaceutical Research."
Berries
In the world of phytonutrient superfoods, there is seemingly a headline every week about a new berry and its star-status nutritional value. Every berry has its day, and for the most part, the buzz bears out under scientific scrutiny. Blueberries contain 2,400 ORAC units per 100 g, blackberries provide about 2,000 ORAC units, strawberries 1,540 ORACs and raspberries contain 1,200 ORACs. A study on antioxidant activity in several berry and plant extract products published in the 2010 issue of the journal "Roczniki Pantswowego Zakladu Higieny" found substantial antioxidant capacity in chokeberry, cranberry and blueberry, using three separate methods of antioxidant testing.
Walnuts and Almonds
Take a nutty perspective for better antioxidant status. Walnuts, at 3,400 ORAC units per 100 g, have received a lot of attention for their heart-healthy antioxidant activity. Almonds, at 1,300 ORACs per 100 g are also a popular antioxidant source. One study found that almonds decreased lipid oxidation, possibly due to phenolic antioxidant compounds present in almonds. In the study, published in the December 2010 issue of the "Journal of Alternative and Complementary Medicine," participants ate 60 g of almonds per day for four weeks and showed lower cholesterol levels along with lower levels of oxidized cholesterol.
Spinach and Kale
Green vegetables, such as spinach and kale, contain significant antioxidant levels, and their ORAC values of 1,770 per 100 g and 1,260 per 100 g reflect that. In a study on antioxidant activity of spinach in laboratory animals, researchers found that spinach extract decreased inflammation and protected against formation of reactive oxygen molecules and intestinal injury. The researchers concluded that the antioxidant effects of spinach may useful in patients with drug-induced intestinal injuries and other inflammatory diseases. The study was published in the August 2010 "Journal of Medical Investigation."
References
- "Bioscience Biotechnology and Biochemistry"; Characterization and Antioxidative Properties of Oligomeric Proanthocyanidin from Prunes, Dried Fruit of Prunus Domestica L.; Kimura Y., et al; September 2008
- RaySahelian.com: ORAC Value of Foods, Acai, Mangosteen and Others
- USDA: High-ORAC Foods May Slow Aging; Judy McBride; Feb. 8, 1999
- "Journal of Alternative and Complementary Medicine"; Effects of Almond Dietary Supplementation on Coronary Heart Disease Lipid Risk Factors and Serum Lipid Oxidation Parameters in Men with Mild Hyperlipidemia; Jalali-Khanabadi B.A., et al; December 2010
- "Journal of Medical Investigation"; Protective Effects of Glycoglycerolipids Extracted from Spinach on 5-fluorouracil Induced Intestinal Mucosal Injury; Shiota A., et al; August 2010
- "Roczniki Pantswowego Zakladu Higieny"; Evaluation of Selected Food Supplements Containing Antioxidants; Lastawska K.; 2010
