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Cancer-Fighting Antioxidant Levels in Organic Foods 30% Higher Than Conventional Foods

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Organic Center Report Indicates Organic Foods Have Elevated Levels of

News Release For more information, contact:
Charles Benbrook, Chief Scientist, Organic Center
(208) 263-5236;, or
Lisa Bell, Crescendo Communications
(303) 527-0203;

Certain Organic Farming and Food Processing Techniques Can Increase
Antioxidant Levels

FOSTER, R.I. January 26, 2005 - The Organic Center's second State
of Science Review (SSR) concludes that organic farming methods have the
potential to elevate average antioxidant levels, especially in fresh
produce. Charles Benbrook, Ph.D., compiled and analyzed existing scientific
information for his report, Elevating Antioxidant Levels Through Organic
Farming and Food Processing. The report reveals that on average, antioxidant
levels were about 30 percent higher in organic food compared to conventional
food grown under the same conditions. An executive summary and the entire
report can be found at:

The report's findings are particularly useful for consumers who wish to
consume higher levels of antioxidants in fresh fruits and vegetables,
without additional caloric intake. The USDA is currently recommending higher
daily intake of fruits and vegetables, especially those that are antioxidant
rich. The report's tables include rankings of common foods according to
their total antioxidant capacity per calorie and per typical serving.
Consumers who seek out foods high in antioxidant content can meet
recommended antioxidant intake levels with less than 10 percent of their
daily caloric intake.

"Because of the many potential health benefits associated with antioxidant
consumption, increasing average daily antioxidant intake through the diet
has emerged as an important health goal," says Benbrook. "This goal was a
major factor shaping the new USDA Dietary Guidelines for Americans, which
increase the average recommended intake of fruits and vegetables to at least
nine servings per day from the original five*. By generating higher
concentrations of antioxidants in fresh produce and other organic foods,
organic farming can help people increase their daily consumption of
antioxidants without a proportional increase in calories."

This report reviews, among other data, 15 quantitative comparisons of
antioxidant levels in organic versus conventional fruit and vegetables.
Organically grown produce had higher levels in 13 out of 15 cases. On
average, the organic crops contained about one-third higher antioxidant
and/or phenolic content than comparable conventional produce. Several
studies found levels of specific vitamins, flavonoids or antioxidants in
organic foods to be two or three times the level found in matched samples of
conventional foods. In studies making direct comparisons of levels of
antioxidants in organic versus conventional produce, higher levels are often
found in organic produce but the converse is rarely true.

Organic farming techniques can increase antioxidant content

A wide range of factors can influence the mix of antioxidants that a plant
manufactures, as well as the levels the plant produces at any given point.
In general, factors that impose stress on plants tend to trigger a plant's
innate defense mechanisms and these mechanisms are driven by and/or entail
the synthesis of antioxidants.

Studies reviewed in this SSR provide evidence that several core practices on
organic fruit and vegetable farms ‹ use of compost, cover crops, slow
release forms of nitrogen ‹ can increase antioxidant and polyphenol content
compared to conventional practices that depend on commercial fertilizers and
pesticides. The prohibition of pesticides in organic farming practices
provides additional benefits to consumers who choose organic.

"Harvesting fruits and vegetables at optimal ripeness and consuming them in
less-processed forms, without removing skins or peals, will preserve a
greater portion of their antioxidants," says Benbrook. "The outer layers of
fruits and vegetables generally contain the highest concentrations of
antioxidants, but many consumers peal their conventionally-grown fruits and
vegetables to help reduce levels of pesticide residues. Seeking out organic
produce can therefore deliver a dual benefit to consumers by maximizing
antioxidant intake and minimizing pesticide dietary exposure."

Organic processing methods may also increase antioxidant levels

There are significant differences between some of the food processing
methods and technologies used in manufacturing conventional foods in
contrast to those allowed and used in producing organic processed foods.
Some of these differences are known to have an impact on antioxidant levels.
For example, the synthetic chemical hexane is often used in extraction of
oils from crops in conventional oil processing plants, but is prohibited in
organic oil processing. Hexane is known to promote removal of certain

High-temperature and high-pressure processing technologies also tend to
remove significant portions of the antioxidants present in fresh foods.
Organic processing plants often use lower pressure, cold-pressing methods to
extract juices and oils. The resulting food products are generally richer
in flavor and retain more nutrients, including antioxidants.

Though there is much more to learn, the current state of science supports
the conclusion that organic farming methods can and often do result in
higher antioxidant levels in fruits and vegetables. This health benefit for
consumers joins the list of other well-documented reasons to buy organic,
including the reduction of farm worker and consumer exposures to pesticides,
the impacts of pesticides on the environment, and the prevention of problems
associated with hormone and antibiotic use in livestock farming. Many
consumers report that they enjoy the richer flavors in organic food and
instinctively sense that organic foods are better for them; this SSR
confirms that there are good reasons to focus additional scientific
resources on gaining a more comprehensive understanding of the taste and
health-oriented benefits associated with elevating average antioxidant
levels in food.

Research on antioxidant levels in organically grown food is among the
Organic Center's top research priorities. The Center has initiated and
funded three new research projects in 2004 focused on the impact of organic
farming methods and food processing technologies on the antioxidant content
of food. Detailed information about the Center's antioxidant-related
projects can be found at


*Source: 2005 USDA Dietary Guidelines for Americans;