Berries, Beans Top 'Best Antioxidants List'
Look for color when searching for these cancer fighters, experts say
MONDAY, June 28, 2004 (HealthDayNews) -- A variety of veggies, fruits and nuts battled it out this month for the top spot on a new list of the 20 most antioxidant-rich foods, ranked by nutrition scientists at the U.S. Department of Agriculture (USDA).
In the end, small red beans won the day, narrowly beating out wild blueberries as the food with the highest concentration of disease-fighting compounds per serving.
Antioxidants fight damage to cells from rogue molecules called "free radicals." Experts believe this assault on cells may fuel killer diseases such as heart disease and cancer, and even aging itself.
The new Top 20 list, published in the June issue of the Journal of Agricultural and Food Chemistry, "is a relative ranking of the capacity of foods to interfere with or prevent oxidative processes and to scavenge free radicals," explained list co-creator Ronald L. Prior, a USDA nutritionist and research chemist based in Little Rock, Ark.
Prior and his colleagues used the most advanced technologies available to tabulate antioxidant levels in more than 100 different types of fruits, vegetables, berries, nuts and spices.
Their Top 20:
- Small red beans (dried).
- Wild blueberries.
- Red Kidney beans.
- Pinto beans.
- Blueberries (cultivated).
- Artichokes (cooked).
- Red Delicious apples.
- Granny Smith apples.
- Sweet cherries.
- Black plums.
- Russet potatoes (cooked).
- Black beans (dried).
- Gala apples.
There's "still a lot we haven't learned" about why some foods are richer in antioxidants than others, Prior said. Even though the small red bean came out on top, "we don't have a lot of information on beans," he added.
Berries are better understood. "The components that contribute a lot of the antioxidant activity are what are called anthocyanins, the compounds that give many berries their dark blue color," he said.
In fact, color may be key to spotting foods that fight free radicals, said Roberta Anding, an American Dietetic Association spokeswoman and a nutritionist at Texas Children's Hospital in Houston.
"If you're looking for the best places to get antioxidants, I will usually tell folks to look at the colors of the rainbow," she added.
For example, "you'll find lutein with some of the yellow pigments found in corn; orange can be the pigments from the carotenoid family that are found in cantaloupe, butternut squash and mango; red could come from things like lycopene, found in tomatoes and watermelon. And then the darker colors -- the purples, blues, in berries," she said.
But Prior cautioned that just because a food has proven to be antioxidant-rich in the USDA's lab, that doesn't mean all those nutrients will be successfully absorbed by the human digestive tract.
"As we learn more and more, we're finding that, depending on the chemical makeup of antioxidants in different foods, some of them aren't apparently absorbed as well, or else they are metabolized in a form where they are no longer antioxidants," he said.
Whether a food is eaten fresh, frozen, processed or cooked can also affect its antioxidant potency -- for good or ill, he said. Blueberries are best when eaten fresh rather than cooked in a pie, for example. On the other hand, research has shown that gentle cooking raises the antioxidant power of tomatoes, he noted.
Although experts are working hard on the project, ongoing efforts to come up with daily dietary guidelines for antioxidant consumption will be "a long process," Prior said.
"How antioxidants behave, how they act within the body, the dose-response -- we just don't know enough about it," he said.
For her part, Anding said people shouldn't get too hung up on gorging on one particular food, but "cast your net widely," eating generous daily servings of a variety of fruits, vegetables and other wholesome foods.
Looking over the USDA's list, Anding suggested creating what she called an antioxidant "power salad."
First, she said, "put together a salad with a variety of mixed greens. Then I'd throw in some dried cranberries or blueberries from the health food store, toss in a few nuts, with a low-fat salad. Again -- choosing from the colors of the rainbow."
Check out the U.S. Centers for Disease Control and Prevention for its Color Your Way to 5 A Day antioxidant-rich diet plan.