Oxidative damage to cells is thought to culminate in the onset of several maladies associated with aging. But foods that score high in antioxidant capacity may protect cells and their components from such damage. While berries, fruits, and vegetables are known to have antioxidant power, many herbs used to flavor our foods are proving to have more, ounce for ounce. But their potency can vary, depending on species and growing conditions.

Now, a variety of fresh culinary and medicinal herbs has been grown under the same environmental conditions, at the same location, and evaluated for antioxidative activity. They've been measured for their ability to disarm oxidizing compounds that our bodies naturally generate as a byproduct of metabolism. Three different types of oregano - Mexican, Italian, and Greek mountain - scored the highest, even higher than vitamin E. Also, they were comparable to the food preservative BHA against fat oxidations. Sweet bay, dill, and winter savory also showed strong antioxidant activity. Medicinal herbs generally scored lower in antioxidant activity, suggesting that their health benefits stem from other types of activity in the body.

Shiow Wang, USDA-ARS Fruit Laboratory, Beltsville, Maryland; phone (301) 504-5776.

"Science Update" was published in the November 2002 issue of Agricultural Research magazine.