Many people forget that chocolate comes from a plant - just like all the fruits and vegetables recommended for a healthy heart.

Cocoa beans, chocolate's main ingredient, are a highly concentrated natural source of flavanol antioxidants, and can play a vital role in daily health-care.

Dark chocolate, in particular, with its blend of rich, delicious, velvety tastes, typically has a higher percentage of cacao solids - cocoa, chocolate liquor and cocoa butter - than milk chocolate.

"More than a to-die-for treat, it is the healthiest type because of the higher cocoa content. Dark chocolate with its high cocoa content does have positive effects on health," says Christian Rast, chief pastry chef of Hilton Shanghai hotel.

"Antioxidants block free radicals that can damage the arterial wall. As well, it is a stimulant to get into a good mood and help to prevent heart attacks," Rast says.

Rast adds that if the cocoa beans come from one plantation, the taste can be surprisingly different compared with that from other plantations even close by - like wine from different vineyards.

The levels of flavanol antioxidants in chocolate products are almost perfectly correlated with the concentration of natural cocoa in products. In general, the higher the natural cocoa content, the greater the flavanol antioxidant levels, according to a study sponsored by the Hershey Co, the major chocolate manufacturer in North America.

Flavanol antioxidants occur naturally in some plant-based foods, such as tea, grapes, blueberries, cranberries and cocoa beans. Cocoa beans are the basic ingredient of all chocolate products. Interestingly, it is one of the most concentrated natural sources of flavanol.

"In their protection of body cells, the antioxidants transfer free radicals that develop on the walls of blood vessels and can cause cancer, aging and atherosclerosis," Rast says. "It is known that the antioxidant concentration is higher in dark chocolate than in food like grapes, nuts and green tea."

Dark chocolate has better antioxidant properties as well. Antioxidants are compounds that help neutralize free radicals and protect the body against their destructive effects, which means that it can protect the heart and arteries from oxidative damage, similar to the rust that develops on metal over time.

A standard serving of dark chocolate (40 grams) provides more antioxidant power than the standard servings of many other well-known antioxidant-containing foods, including blueberries, walnuts and raisins.

Scientists are still investigating how antioxidant values in foods relate to antioxidant activity in the body, and more research needs to be done to better understand how the body absorbs and uses these antioxidants.

Consumers, when choosing dark chocolate in shops, can first judge from the look. High-quality chocolate usually has a shiny and smooth surface. Secondly, taste is the key. An authentic dark chocolate brings a wonderful feeling as it melts in the mouth. Chewing poor quality chocolate is like chewing gum.

Like everything too much is not good. While a little dark chocolate is good, a lot is not better. Chocolate is loaded with calories and should be enjoyed in moderation. Remember that a balanced diet - and plenty of exercise - is still the key to a good health.

(Shanghai Daily March 24, 2009)