In addition to a morning jolt, coffee gives the average American almost 1,300 mg daily of antioxidants in the form of polyphenols, substances found in plants that may be more important than vitamins C and E when it comes to preventing disease, said Joe Vinson, Ph.D., of the University of Scranton in Scranton, Pa.
Coffee far outstrips the second and third dietary sources of polyphenols in the United States: black tea (294 mg) and bananas (76 mg), Dr. Vinson reported at the national meeting of the American Chemical Society here on Sunday.
Dr. Vinson and colleagues analyzed the polyphenol content of more than 100 different foods and beverages, including vegetables, fruits, nuts, spices, and oils. In addition to absolute polyphenol content, however, the researchers also considered the amount of each food the average American consumed daily. Data on U.S. per-capita consumption of these foods was obtained from the U.S. Department of Agriculture.
The remaining items in the top ten dietary sources of polyphenols included dry beans (72 mg/day), corn (48 mg/day), red wine (44 mg/day), beer (42 mg/day), apples (39 mg/day), tomatoes (32 mg/day), and potatoes (28 mg/day).
Does this mean people should drink more coffee instead of eating their fruits and vegetables?
No, Dr. Vinson said. "Unfortunately, consumers are still not eating enough fruits and vegetables, which are better for you from an overall nutritional point of view due to their higher content of vitamins, minerals and fiber," he said.
Fruits such as dates, cranberries, and red grapes have some of the highest concentrations of antioxidants per serving size, he noted. However, these foods are consumed less frequently by Americans than coffee.
Although some studies have linked coffee to potential health benefits, such as protection against liver and colon cancer, other studies have tied it to high blood pressure and elevated heart rates, Dr. Vinson said. Therefore, he recommends moderation when it comes to coffee drinking.
"One or two cups a day appears to be beneficial," he concluded.
- Reviewed by Robert Jasmer, MD Associate Clinical Professor of Medicine, University of California, San Francisco
American Chemical Society 230th National MeetingSource Reference: Vinson JA et al. Polyphenols: total amounts in foods and beverages and U.S. per capital consumption. Abstract number AGFD 10. Presented at the American Chemical Society 230th National Meeting in Washington, D.C. August 28, 2005.