Antioxidant controversy: Scientists seek measurement standards

An international gathering of researchers from 19 countries has agreed for the first time to establish uniform measurement standards for antioxidants. The decision could ultimately produce more reliable data for consumers, who face misleading claims about the amount and effect of these disease-fighting compounds in their food, health and beauty products, the researchers say.

The historic three-day meeting, the First International Congress on Antioxidant Methods, was held June 16-18 in Orlando, Fla. The 144 scientists and experts from industry, academia and government who attended the meeting discussed the latest claims in antioxidant research and identified methods used to make these claims. The principal sponsor of the meeting was the American Chemical Society, the world's largest scientific society.

The result: Widespread agreement that antioxidant measurements need to be standardized but disagreement on the best method to measure the beneficial compounds, which are thought to reduce the risk of cancer and heart disease as well as fight aging, arthritis and Alzheimer's disease.

"Right now, it's difficult to compare the antioxidant content of a can of blueberries to a fruit smoothie," said John W. Finley, Ph.D., chair of the meeting organizing committee and an associate editor of the ACS Journal of Agricultural and Food Chemistry. "There's no uniformity in the way antioxidants are evaluated. You don't know what you're getting, and that's not fair to consumers."

One of the most heated issues at the meeting concerned the identification of the most reliable values for antioxidant measurements. Finley estimates that there are currently between 25 and 100 different methods used to measure antioxidants. "A little difference in methodology can make a huge difference in results," cautioned Finley. "We need to identify the four or five best methods and make them consistent."

"As a result of intense debate, we made progress toward developing uniform methods," declared Finley, who is Chief Technical Officer at A.M. Todd Company in Montgomeryville, Pa., a leading supplier of botanical extracts. A multidisciplinary group of scientists will now begin working together to set standards on the methodology used to measure antioxidants, he said.

Publication of preliminary recommendations from the meeting is tentatively scheduled for September, Finley said. Official standard methods could take two to three years to develop and must be tested in multiple labs to ensure the methods are valid, he noted.

Once official standards are established, the Journal of Agricultural and Food Chemistry will become the first peer-reviewed scientific journal to require that contributors adhere to agreed-upon standards in reporting new antioxidant measurement methods and in measuring antioxidant levels in samples, said Finley, adding that other scientific journals also will be expected to follow these standards.

Some meeting participants felt the intense focus on methodology distracted from the real significance of antioxidants for consumers, which is their potential health benefit. Antioxidant news is increasingly capturing the attention of health-conscious consumers, but there is little scientific data on the actual effect of these compounds in humans. More studies are needed in this area, researchers said.

"The bottom line is the same: eat more fruits and veggies," said Ronald L. Prior, Ph.D., a meeting co-organizer and lead author of a recent U.S. Department of Agriculture study that is considered the largest, most comprehensive analysis to date of the antioxidant content of commonly consumed foods.

Represented at the meeting were the National Institutes of Health, the USDA, the American Oil Chemists' Society, the Association of Analytical Communities, as well as a host of universities and food-related organizations. A second meeting on antioxidant methods is expected to take place next year, Finley said, adding that he hopes to expand the meeting to include more participation from the dietary supplement and cosmetic industries.

Mark T. Sampson, 30-jun-2004