We all know that chocolate is good. It tastes good. And there are all those studies that say it's good for you, too. What did they say? That it was good to eat chocolate -- dark chocolate, if I remember correctly. Something about antioxidants... something about warding off cancer.

Until now, the mechanism behind how cocoa may stave off tumors, after the sweet goodness works its magic on the tongue, has remained unclear. A study published recently in The Journal of Biological Chemistry shows just how cocoa may be beneficial.

Using mouse skin cells grown in petri dishes, the researchers determined that a compound in cocoa may reduce the likelihood of developing tumors. The compound, procyanidin (the scientists extracted it from a commercial cocoa powder), may accomplish this by hampering the inflammation response.

The link between inflammation and cancer is well established. This study determines which players in the inflammation process (triggered by tumor growth) are affected by the cocoa component -- e.g. COX-2 triggers the inflammation response but is suppressed by procyanidin.

Procyanidin, a flavonoid, found in good things like tea, red wine, and cocoa, is likely an antioxidant. While it's possible that the protective effects are independent of the antioxidant properties, it is clear that procyanidin is busy working at the molecular level. By binding a protein called MEK1, a cascade of signals is blocked. The result: fewer tumors -- or at least, less clumpy goop growing in the dish.

This study helps explain previous reports in which rats exposed to carcinogens were significantly protected when fed a cocoa liquor. Cocoa beans, rich with procyanidin, contain other goodies too. However, another prominent compound, theobromine -noted for its stimulatory effect- did nothing to quell the unwanted petri dish blobs. Though I'm sure it still contributes to the whole of what makes cocoa good.