In terms of weight, many herbs offer higher levels of antioxidants than fruit, vegetables or berries, according to a new study conducted by researchers at the ARS Fruit Laboratory in Beltsville, Md.

The project saw the scientists evaluate the antioxidant levels in a variety of 27 fresh culinary and 12 medicinal herbs grown under the same environmental conditions at the ARS National Arboretum in Washington, DC. The test, known as the ORAC test, found that three different types of oregano scored highest in terms of antioxidant activity. The herb beat vitamin E and was noted to be comparable to the food preservative BHA against fat oxidation.

Other culinary herbs such as rose geranium, sweet bay, dill, and winter savory also showed strong antioxidant activity. The medicinal herbs generally scored lower, however, which suggests that their health benefits lie in other bodily functions.

Reporting the findings in a recent issue of the Journal of Agricultural and Food Chemistry, ARS plant physiologist Shiow Wang warned that the antioxidant activity of these herbs may vary depending on where they are grown.

Antioxidants are believed to be useful in protecting human cells from oxidative damage caused by aging; they work by disarming oxidizing compounds produced naturally by our bodies as a byproduct of metabolism.