A 2004 study conducted by the USDA found that certain varieties of dried beans contain high levels of antioxidants, but Americans commonly eat more canned beans, observes scientist Mark Brick, PhD. To find out if canned have as many antioxidants as dried, Brick and a team of researchers at Colorado State University measured the phenolic and flavonoid contents of several types of canned commercial beans for a 2009 study published in Crop Science. The scientists found that while all canned beans contain antioxidants, small red beans have the highest levels, followed closely by dark red kidney and black beans. In fact, darker canned beans have as much as 3 times more phytochemicals — plant compounds that wipe out free radicals to protect your cells and repair DNA damage — than white kidney and great Northern beans.
Love yogurt? You'll love this stat: Just 1 cup of low-fat plain yogurt provides at least 25% of the daily value for riboflavin — the same that's in 1 cup of boiled spinach. While not an antioxidant itself, riboflavin (a B vitamin) is critical in promoting antioxidant activity. Without it, the antioxidant glutathione — which is already in our cells — cannot destroy free radicals, which may lead to an increased risk of heart disease, cancer, and other chronic conditions. Because riboflavin is water soluble, it remains in the body only a few hours and must be replenished daily; yogurt does the trick.
6. Canola Oil
Heart-healthy canola oil (which is less expensive and milder tasting than olive oil) is rich in the antioxidant alphatocopherol, according to Maret Traber, PhD, of the Linus Pauling Institute at Oregon State University. Just 1 tablespoon contains 16% of the DV. Alphatocopherol is one of eight antioxidants in vitamin E, which scientists have found keeps the fats in "bad" LDL cholesterol from oxidizing and forming free radicals, potentially leading to cardiovascular diseases and other chronic conditions. Turns out, though, we aren't getting enough of this potent antioxidant. Close to one-third of women have low concentrations of alpha-tocopherol, say researchers who looked at data from a national nutrition survey conducted by the CDC. Easy fix: Use canola oil when baking or anytime you need a neutral-tasting oil for saut?ing.
7. Organic Milk
Switch from regular milk to organic and you'll be rewarded with a stronger dose of antioxidants, including vitamin E and the carotenoids beta-carotene and lutein, says Gillian Butler, PhD, coauthor of a recent British study published in the Journal of the Science of Food and Agriculture. Butler's findings show that the antioxidants in milk from cows raised on organic or grass-fed diets are about 40 to 50% more concentrated than the milk from conventionally raised cows. These cows eat more grass, and the pasture itself provides more antioxidants than grain feeding even if the feed is augmented with supplements. If you're not a frequent milk drinker, look for cheese and butter from grass-fed cows; they also offer more antioxidants than conventional varieties, says Butler.
8. Natural Sweeteners
The average American consumes 130 g of added refined sugars each day. If you cut excess sugar and use natural sweeteners like molasses, honey, brown sugar, and maple syrup instead of refined whenever possible, you can add the equivalent of antioxidants from an extra serving of nuts or berries to your daily diet. That's according to researchers at Virginia Tech University who examined the antioxidant content of several natural sweeteners and found that molasses (particularly dark and blackstrap varieties) had the highest amounts. Their study, published in the Journal of the American Dietetic Association, showed that honey, brown sugar, and maple syrup also contained significant levels of antioxidants. While the university study looked at commonly available commercial honeys (usually refined from clover nectar), earlier studies have measured antioxidants in a variety of honeys and found that darker types tend to have significantly higher polyphenol counts. For example, buckwheat has an antioxidant level 8 times higher than clover, which is also outranked by sunflower and tupelo honeys.