Pliny the Elder, the ancient Roman philosopher, praised radicchio for its medicinal properties, claiming that it was useful as a blood purifier and natural sedative for insomniacs.Maybe he was on to something! Italian researchers recently tested 40 vegetables for phenolic content — and radicchio landed in the top four.

A member of the chicory family, radicchio have firm, white-veined, red or purple leaves with a slightly bitter taste. A popular salad ingredient, radicchio is included in seven of Dole’s packaged salads, such as the Mediterranean and European blends. One 9-calorie cup of radicchio boasts an impressive 128% of your vitamin K needs, which helps support bone health and may also reduce insulin resistance. Perhaps more astonishing is how radicchio reigns supreme in the produce aisle in terms of its high concentration of phenols — plant compounds that may have antioxidant properties.

In a study published in the British Journal of Nutrition, 40 vegetable varieties were analyzed for total phenolic content.Radicchio was higher in total phenols compared to all the other lettuces tested — and indeed had 236% more polyphenols than three types of green leaf lettuce.Radicchio’s polyphenol content was also much higher compared to other veggie staples: 684% higher than cucumbers, 119% higher than broccoli and 245% higher than beet greens.Of all the different plant foods tested, highest of all in polyphenols, in descending order, were violet artichokes, red chili peppers, red beets and radicchio.

Polyphenols are thought to help neutralize dangerous free radicals which increase the oxidation (think “rust”) of otherwise healthy cells. By making radicchio your go-to salad ingredient, you’ll not only help build your polyphenolic reserves, you’ll get all the other benefits associated with frequent salad consumption, including mental sharpness, keen eyesight and lower incidence of stomach flu.

Published February 1, 2012