If you’ve ever made a fruit salad, you probably know that squeezing lemon juice onto the apples, pears, and bananas will keep the fruit from turning brown. This brown color happens because of a process called oxidation—a reaction between the oxygen molecules in the air and the molecules in the substance the air meets.
A similar type of reaction happens inside your body all the time. Substances called oxidants, or free radicals, react with your cells, harming healthy tissue, weakening immunological functioning, speeding up the aging process, and contributing to chronic degenerative diseases. These free radicals are formed through normal body processes, as well as through environmental exposure to the sun, pollution, cigarette smoke, too much stress, and the intake of alcoholic beverages and unhealthy food. Antioxidants are substances that work like that lemon juice on the fruit, protecting healthy tissue by destroying free radicals before they do any damage. Antioxidants are believed to play a role in helping to fight and prevent cancer, heart disease, Alzheimer’s disease, and other chronic conditions.
So, how do you get these magical antioxidants to work for you? Not surprisingly, a healthy diet full of a variety of fruits and vegetables will do the trick. But are all fruits and vegetables created equally when it comes to antioxidant benefits? Not necessarily!
In a study published in the July 9, 2004 issue of the Journal of Agricultural and Food Chemistry, the USDA analyzed over 100 different foods and their antioxidant levels. Each food item was ranked according to its antioxidant concentration and its antioxidant capacity per serving size.
The results may surprise you. Topping the list were small red beans and wild blueberries. Cranberries, red kidney beans, and artichokes also ranked very high, and unexpected contenders included pecans and ordinary russet potatoes.
However, every study has its drawbacks. Researchers say that although the data can help guide consumers who wish to include more antioxidants in their diet, the health benefits of these foods may not be directly proportional to their antioxidant content. So, even though small red beans have the most antioxidants, they may not offer the greatest overall health benefits when you consider the other nutrients they contain (or lack). Keep in mind that the health benefits of antioxidant-rich foods depend on how the foods are absorbed and utilized in the body, and this varies depending on the food (and where it was grown, how it was grown, when it was harvested and more).
For reference, here are the top 20 antioxidant-rich foods in the USDA study, in order from greatest to lowest levels of antioxidants.
Researchers and scientists are currently trying to come to a consensus to provide guidelines for antioxidant intake, much like the guidelines the government provides for vitamin and mineral intake. This USDA study will probably help this process along, but such guidelines are still probably far away. However, you don’t have to wait for these guidelines to start improving your diet! Aim for a variety of fruits and vegetables, as always, and try to incorporate many of the fruits, vegetables and nuts that rank high in the USDA antioxidant study–in addition to other whole, nutritious foods that aren’t on the list. And remember that how you prepare these foods makes a difference, too; deep-fried russet potato “fries” and sugary blueberry pie will still probably do more harm than good!