An In-Depth Guide To High-Antioxidant Food

What Exactly Are Antioxidants?

One cup of green tea provides 10 to 40mg of polyphenols and has antioxidant effects greater than a serving of broccoli, an antioxidant-rich food. The high antioxidant activity of green tea makes it beneficial for protecting the body from damage due to free radicals. Research shows that the EGCG in green tea may help the arterial wall by reducing lipids; green tea can protect against experimentally induced DNA damage, and much more. A 2006 study* showed that elderly Japanese people who drank more than 2 cups of green tea a day had a 50% lower chance of cognitive impairment than those who drank less green tea, or who consumed other tested beverages. The high amount of catechins in green tea are believed to be responsible.

*The American Journal of Clinical Nutrition, Vol. 83, pp. 355-361.

Sounds good, but how much of that was truly comprehensible? The media is full of news about antioxidants...free radicals...EGCG...catechins. But what do these terms mean? Much of the “antioxidant” chatter flies over most people’s heads. Don’t worry—we’ve provided a glossary of antioxidant terms and definitions. Here’s an overview of how it all works for a popular antioxidant foods, green tea and white tea:

There are many antioxidants with different degrees of strength. Green tea and white tea contain a particularly strong antioxidant, the catechin EGCG. Catechins are flavonoids, a subgroup of polyphenols, which are substances found in plants. Green and white teas have different catechins from black tea and oolong tea, due to lesser processing (green and white teas are not oxidized; oxidation inactivates the catechins). To look at the relationship visually:

With this basic introduction, you can plunge into the glossary of antioxidant terms and definitions, or skip ahead to look at foods that are high in antioxidants. Click the links below to discover more about antioxidant terms.

• Antioxidant Terms & Definitions A To E
• Antioxidant Terms & Definitions F To M
• Antioxidant Terms & Definitions O To Z

Antioxidant-Rich Foods

Aside from açaí and whatever the next superberry will be, cacao is king...but like cocoa and chocolate, it’s tough to consume enough to reap antioxidant benefits without ingesting a lot of sugar in the process. The beauty of tea over all other foods is that you can enjoy it calorie-free and relatively effortlessly, wherever you are. But to eat a well-rounded, antioxidant-rich diet, there’s a broad shopping list below.

Note, though, that it isn’t easy getting an accurate read on ORAC values: Measurements are made using different scales, making it difficult to compare. Some evaluations compare units per grams of dry weight, others use wet weight, others use units per serving. Thus, if one picks and chooses numbers from different reports, different foods can appear to have comparatively higher or lower ORAC values than they actually do. Thus, for example:

• A raisin has no more antioxidant potential than the grape from which it was dried, yet raisins have a much higher ORAC value per gram wet weight than grapes, due to their reduced water content. (They also are high in calories.)

• Similarly, fruits with high water content can appear to be very low in antioxidants.

• Higher-quality produce can yield higher ORAC levels.

• No one is yet comparing the ORAC value per calorie. Montmorency cherries have much higher ORAC values, as well as many more calories per serving than blueberries (Montmorency cherry juice has 12,800 ORAC units per 100 grams).

Issues With Evaluating Antioxidant Foods

There are several issues that need to be addressed,* that will take years to sort out. So, it’s good to eat “high antioxidant foods.” But unlike other prescriptions for health—an aspirin a day can help ward off heart attacks, for example—no one can tell you how much of the antioxidant food will have the desired effect.

*Thanks to reader Diane Welland, M.S., R.D., a food and nutrition writer, for contributing some observations.

ORAC Values Can Compare “Apples & Oranges”

Even if there were an unassailable list of apples-to-apples ORAC values for all antioxidant foods, we are still waiting for the clinical research that indicates what
quantities of the food are required to have an optimal (or even basic) antioxidant effect. The various studies present their numbers in different ways, not only for ORAC values (which vary depending on the lab and the way they assay), but also on measurements of different antioxidant evaluations such as TAC (total antioxidant capacity) and FRAP (ferric ion reducing antioxidant power).  Most serving sizes are based on 100 gram portions (3-1/2 ounces), which may be relevant in some foods, like berries, but totally unmanageable in categories like spices (who can eat 3-1/2 ounces of tarragon or oregano) or chocolate and nuts (the calories alone would contribute to a weight problems—as noted above, 3-1/2 ounces of chocolate is three portions on any normal diet).

The Efficacy Of Antioxidants In Different Foods

There may not be a direct relationship between ORAC value and the food ingested for
efficacy—how much of a specific antioxidant is effective against a specific condition. Do you need the same amount of green tea catechins—whether ounces, teaspoons or cups, or other measure—to (as is suggested by studies) protect against lung, prostate and breast cancer as you do, need, say, cacao flavonoids to inhibit the platelet aggregation that can cause a heart attack or stroke?

Otherwise stated, think of having to eat/ drink eight cups of tea per day versus eight cups of of chocolate. One has zero calories, the other, even made with water and artificial sweetener, will rack up quite a calorie tab.

How Much Do You Need To Eat For “Benefits?”

There are no “generic” antioxidant benefits. Each food’s phytonutrients appear have a
different efficacy—be it to suppress liver cancer, breast cancer, Alzheimer’s or other disease. Given how early we are in our understanding of how any particular antioxidant effect works in humans, it will be years before anyone knows, e.g. how many blueberries a day keep the doctor away, versus how much mangosteen, versus açaí, cranberry, cacao, etc. Some foods can engender a practical challenge. The curcurmin in the spice turmeric is a powerful antioxidant, with anti-inflammatory, antibacterial, stomach-soothing, and liver- and heart-protecting effects. Certainly, it will be a challenge for many to work a teaspoon—much less 3-12 ounces—into a daily food plan.

Does Antioxidant Capacity Decline With Freshness? What happens to fruits and vegetables—particularly the highly-touted rainforest fruits—that are not grown domestically and have to be shipped from so far away? We know that sugars and other components begin to convert as soon as fruit is picked; does this happen with antioxidants as well? Some fruits like açaí don’t travel well and are processed into  juice immediately, but what about mangosteen?

What Happens When You Cook The Food? Preparation and cooking effect
antioxidants, but studies have just begun to scratch the surface here.  Raw isn’t always best when it comes to fruits and vegetables; studies have shown that canned tomatoes have more antioxidants than the raw fruit. Certain cooking and preparation methods can increase the antioxidant power, either by breaking down cell walls and releasing more of the phytonutrient, or by increasing absorption (combining olive oil with canned tomatoes is an example of this).

What About Açaí?

The açaí berry (pronounced ah-sigh-EE) from the Brazilian rainforest has been trumpeted as the next important food, a true superfruit. It may in fact be one of the most nutritious fruits on the planet: Açaí’s antioxidants are significantly higher than greentea, chocolate or blueberries and 10 times higher than red grapes. It has 10 to 30 times more anthocyanins (flavonoids that bind free radicals) than red wine. Açaí also has a synergy of omega 6 and 9 essential fatty acids (healthyfats), fiber, amino acids and vitamins A and C. 
Photo of açaí berries by Ronaldo Salame.

Great—however açaí is not one of the most palatable fruits. The plain berries are very tart; like eating plain cranberries, very few people enjoy them straight. Brazilians drink açaí in sweetened juices, which are now in U.S. supermarkets in a variety of blends with more familiar fruits (banana, raspberry, etc.).** But not everyone who is health-and-wellness focused wants to add all that sweetened juice to their daily intake (the same is true with cocoa and chocolate, even at 70% cacao). So, tea still looks like a winner: You can drink all you want for zero calories, and even a heaping teaspoon of sugar adds just 25. Note, though, that you can’t add milk: the milk proteins counter the effect of the catechins.

**Naked Juice and Bossa Nova are two brands that offer açaí mixed with other fruit juices; Bossa Nova has a pure açaí sweetened with agave, a honey-like sweetener from the Mexican plant that also is the source of tequila.

Originally Posted By:

KAREN HOCHMAN from The Nibble

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