Daily News Archive
From April 12, 2006
Produce More Nutritious Than Chemically-Farmed Produce
(Beyond Pesticides, April 12, 2006) Organically grown fruits and vegetables, however, are proving to have higher levels of antioxidants, vitamins and minerals than their conventionally grown counterparts.
Donald R. Davis, PhD, a research associate with the Biochemical Institute at the University of Texas, Austin, recently analyzed data gathered by the USDA in 1950 and 1999 on the nutrient content of 43 fruit and vegetable crops. He found that six out of 13 nutrients had declined in these crops over the 50-year period (the seven other nutrients showed no significant, reliable changes). Three minerals, phosphorous, iron and calcium, declined between 9 percent and 16 percent. Protein declined 6 percent. Riboflavin declined 38 percent and ascorbic acid (a precursor of vitamin C) declined 15 percent.
A study of the mineral content of fruits and vegetables grown in Britain between 1930 and 1980 shows similar decreases in nutrient density. The British study found significantly lower levels of calcium, magnesium, copper and sodium in vegetables, and of magnesium, iron, copper and potassium in fruit. The report concludes that the declines indicate "that a nutritional problem associated with the quality of food has developed over those 50 years."
The decline in our produce's nutritional value corresponds to the period of increasing industrialization of our farming systems. As we have substituted chemical fertilizers, pesticides and monoculture farming for the natural cycling of nutrients and on-farm biodiversity, we have lessened the nutritional value of our produce. Integrated well-established organic farming systems can counter the decline.
Research comparing the nutritional value of organic and conventional foods is accumulating rapidly. "What all our data shows," says Charles Benbrook, PhD, chief scientist at the Organic Center and a former executive director of the Board on Agriculture of the National Academy of Sciences, "is that whenever there's been a valid comparison between conventional and organic, organic is virtually never lower than conventional and, in a significant number of cases, it's higher. Sometimes it's significantly higher in several important nutrients."
For example, Virginia Worthington, PhD, a clinical nutritionist who earned her doctorate in nutrition at Johns Hopkins, published a review in 2001 of 41 studies comparing the nutritional value of organic and conventional produce. After tallying the data across all the studies, Worthington concluded that organic produce had on average 27 percent more vitamin C, 21.1 percent more iron, 29.3 percent more magnesium and 13.6 percent more phosphorous than conventional produce.
Dr. Benbrook released a review in 2005 of the research comparing antioxidant levels in conventional and organic foods. In humans, antioxidants reduce damage to cells and DNA from free radicals (molecules generated by metabolic processes within the body), and thereby promote cardiovascular health, inhibit the reproduction of cancerous cells, slow the aging process in the brain and nervous systems, and lessen the risk and/or severity of Alzheimer's, Parkinson's and Huntington's diseases. Benbrook found that in 85 percent of the comparable data points, produce from organic farms had higher levels of antioxidants than did produce from conventional farms. On average, antioxidant levels in organic produce were 30 percent higher.
Earlier this year, a Swedish team of scientists demonstrated that extracts from organically grown strawberries slowed the proliferation of colon and breast cancer cells to a significantly greater degree than extracts from conventional strawberries did. The levels of all the antioxidants analyzed by the team were higher in the organic strawberries than in the conventional.
"As someone that has been involved with science
and science policy for my whole life," says Dr. Benbrook, "I
think the scientific case has been made for organic produce. The case
has been made firmly enough so that it is appropriate and, indeed, irresponsible
at this point not to tell consumers straight up that choosing organic
fruits and vegetables probably delivers nutritional benefits because
of the higher levels of antioxidants and vitamins and minerals."
Source: The San Francisco Chronicle, March 24, 2006
TAKE ACTION: Eat organic food whenever possible. Be sure Look for the USDA Certified Organic Label when buying food for your family.