What Are Anti-Cancer Benefits of Dark Chocolate?

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As foods go, chocolate is controversial. Once praised by the Aztecs for its healing powers, chocolate became much maligned when it was processed with enough milk and sugar to turn it into junk food. Dark chocolate, the closest thing to a cacao bean that still tastes good to eat, is a much better indulgence for your diet -- and scientists have found that it might even protect against cancer.

Chocolate and Antioxidants

Chocolate contains antioxidant compounds known as flavonoids, which are also present in fruits and vegetables. According to the Linus Pauling Institute, flavonoids fight free radicals in the bloodstream, and can also help remove heavy metals, a process known as chelation. Various flavonoids have been found to slow the growth of artificially-induced cancers in experimental models. However, real-life studies have not yet shown any evidence that flavonoids truly fight cancer. In addition, no matter how much chocolate you eat, flavonoid levels in your bloodstream will generally be 100 to 1,000 times lower than levels of other antioxidants, such as vitamin C.

Chocolate and Tumor Growth

In 2005, researchers at Georgetown University found that a compound called pentameric procyanidin was able to deactivate certain proteins in the body, causing them to stop building new tumor cells. Pentameric procyanidin is naturally found in chocolate. However, the study was funded by a major chocolate manufacturer, and the U.K. National Health Service warns against taking this study's findings too seriously. Although the results were promising, they don't represent real evidence that chocolate fights cancer, and much more research is needed.

Current Knowledge

In 2007, the Linus Pauling Institute conducted a research review that led to a surprising conclusion: Though flavonoids are antioxidants, their function within your body is entirely different. It appears that your body treats flavonoids like foreign compounds, and tries to get rid of them. In the process, it produces enzymes that also fight mutagens and carcinogens, thereby boosting its defenses against cancer. Dark chocolate and other flavonoid-rich foods might fight cancer after all, just not in the way previously thought.

How to Eat It

The harsh truth is that vegetables and fruits contain plenty of flavonoids; you don't exactly need to eat chocolate to get cancer-fighting substances. Still, when it comes to pleasurable eating experiences, nibbling on a chocolate bar has very few rivals. When you eat chocolate, stick to dark chocolate with high cocoa content and avoid chocolate with high sugar content. Milk chocolate and alkalized or Dutch-processed cocoa are low on flavonoids, so make sure you read your ingredients list. Watch for high calorie counts and small serving sizes, then enjoy your rich dark chocolate with a side of good health.