Explore the health-promoting properties of flavonoids

Nutrition Health Review, Summer, 1995

ATLANTA - Do plant compounds called flavonoids have the ability to promote health in humans by, modifying the body's biologic responses?

Elliott Middleton, Jr., M.D., professor of medicine at the University of Buffalo, thinks the answer is yes. He has been investigating the function of these low-molecular-weight organic plant compounds for 16 years and has published a number of papers on the subject.

Middleton was invited to review his findings and summarize other flavonoid research at the annual meeting of the Federation of American Societies of Experimental Biology in April 1995.

"Flavonoids have existed in nature for one billion years, so clearly they are doing something very important for plants," Middleton says. "It may be that they are important for humans too, but they haven't been studied sufficiently.

"At present, flavonoids - found in fruits, vegetables, nuts, seeds, stems, bark, flowers, tea and wine - are considered to be secondary, non-essential dietary factors. However, this position may need to be modified in view of their potentially health-promoting activities that have come to be appreciated, at least in experimental settings. They display a remarkable array of biochemical and pharmacological actions, some of which suggest that certain members of this group of compounds may significantly affect the function of many human cells and tissues."

Flavonoids, of which more than 4,000 exist in nature, are responsible for the red, yellow, and orange of flowers, vegetables, and fruit, and for the hues of autumn leaves. They are involved in plant growth, sex determination, nitrogen fixation, respiration, and photosynthesis. They also protect plants from insects and act as antioxidants and sunscreens.

Given this broad range of action in plants, it is reasonable to think they are important micronutrients for humans as well, Middleton asserts.