Artichokes and beans may not be at the top of your list of favorite foods, but when it comes to antioxidants, these veggies earn a coveted place. They are among a growing variety of foods found to contain surprisingly high levels of these disease-fighting compounds, according to a new USDA study, which researchers say is the largest, most comprehensive analysis to date of the antioxidant content of commonly consumed foods.
In addition to confirming the well-publicized high antioxidant ranking of such foods as cranberries and blueberries, the researchers found that Russet potatoes, pecans and even cinnamon are all excellent, although lesser-known, sources of antioxidants, which are thought to fight cancer, heart disease and Alzheimer's. The study appears in the June 9 print edition of the Journal of Agricultural and Food Chemistry, a peer-reviewed publication of the American Chemical Society, the world's largest scientific society.
"The bottom line is the same: eat more fruits and veggies," says Ronald L. Prior, Ph.D., a chemist and nutritionist with the USDA's Arkansas Children's Nutrition Center in Little Rock, Ark., and lead author of the study. "This study confirms that those foods are full of benefits, particularly those with higher levels of antioxidants. Nuts and spices are also good sources."
The new study is more complete and accurate (thanks to updated technology) than previous USDA antioxidant data and includes more foods than the previous study, the researchers say. They analyzed antioxidant levels in over 100 different foods, including fruits and vegetables. In addition, the new study includes data on spices and nuts for the first time.
Among the fruits, vegetables and nuts analyzed, each food was measured for antioxidant concentration as well as antioxidant capacity per serving size. Cranberries, blueberries, and blackberries ranked highest among the fruits studied. Beans, artichokes and Russet potatoes were tops among the vegetables. Pecans, walnuts and hazelnuts ranked highest in the nut category.
Although spices are generally consumed in small amounts, many are high in antioxidants. On the basis of antioxidant concentration, ground cloves, ground cinnamon and oregano were the highest among the spices studied.
Prior says that the data should prove useful for consumers seeking to include more antioxidants in their diet. But he cautions that total antioxidant capacity of the foods does not necessarily reflect their potential health benefit, which depends on how they are absorbed and utilized in the body. Researchers are still trying to better understand this process, he adds.
BEST SOURCES OF FOOD ANTIOXIDANTS: TOP 20 FRUITS, VEGETABLES AND NUTS (AS MEASURED BY TOTAL ANTIOXIDANT CAPACITY PER SERVING SIZE)
In order of rank:
1. Small Red Bean (dried) Half cup
Total antioxidant capacity per serving size 13727
2. Wild blueberry 1 cup
Total antioxidant capacity per serving size 13427
3. Red kidney bean (dried) Half cup
Total antioxidant capacity per serving size 13259
4. Pinto bean Half cup
Total antioxidant capacity per serving size 11864
5. Blueberry (cultivated) 1 cup
Total antioxidant capacity per serving size 9019
6. Cranberry 1 cup (whole)
Total antioxidant capacity per serving size 8983
7. Artichoke (cooked) 1 cup (hearts)
Total antioxidant capacity per serving size 7904
8. Blackberry 1 cup
Total antioxidant capacity per serving size 7701
9. Prune Half cup
Total antioxidant capacity per serving size 7291
10. Raspberry 1 cup
Total antioxidant capacity per serving size 6058
1.1 Strawberry 1 cup
Total antioxidant capacity per serving size 5938
12. Red Delicious apple One
Total antioxidant capacity per serving size 5900
13. Granny Smith apple One
Total antioxidant capacity per serving size 5381
14. Pecan 1 ounce
Total antioxidant capacity per serving size 5095
15. Sweet cherry 1 cup
Total antioxidant capacity per serving size 4873
16. Black plum One
Total antioxidant capacity per serving size 4844
17. Russet potato (cooked) One
Total antioxidant capacity per serving size 4649
18. Black bean (dried) Half cup
Total antioxidant capacity per serving size 4181
19. Plum One
Total antioxidant capacity per serving size 4118
20. Gala apple One
Total antioxidant capacity per serving size 3903