The Sweet Science of Chocolate

This video story was originally produced by Jenny Oh and was updated by Lisa Landers and Arwen Curry.

Chocolate is the solid gold of sweets, providing a standard of delectability that’s been upheld around the globe for more than 2,000 years. The ancient Mayans and Aztecs even used the pods of the cacao tree, which produces chocolate, as currency. They also used cacao as a tonic to improve overall health.

Today’s scientists agree with the ancients: chocolate, in small doses, is not just delicious -- it’s actually good for you. This is particularly true of dark chocolate, which is rich in compounds called flavanols. Also found in red wine, tea and berries, flavanols have an antioxidant effect, reducing cell damage and heart disease. Research also strongly suggests that they support healthy blood pressure and reduce the chances of strokes and heart attacks.

“They’re really good at really scavenging or sopping up these free radicals that can damage your cells,” said Mary Engler, a senior clinician and training director at the National Institutes of Health, NINR, in Bethesda, MD. Engler has studied the health effects of chocolate and other flavonols since 2001.

Pregnant women should take special note: Regular intake of chocolate -- the darker the better -- during pregnancy appears to lower the risk of pre-eclampsia, a dangerous complication. A 2013 study at the University of Helsinki, Finland also showed that women who eat chocolate every day during pregnancy report calmer, happier babies six months after giving birth.

Milk and white chocolate lovers, you're out of luck: you’ll get all the butter, fat, and sugar, but no circulation-boosting flavanols. Even dark chocolate is rich and should be eaten in moderation, and beware: some manufacturers artificially darken their product and remove the bitter cacao solids, which contain the healthy compounds.

As beloved as it is, it’s not surprising that chocolate is an important crop for farmers around the world. Roughly 70 percent of cacao is produced in equatorial Africa, where two million small-scale farms depend on the crop. But cocoa production has long suffered from serious losses due to pests, drought and diseases. A third of the cocoa produced in Africa -- $800 million’s worth -- is lost each year.

Fortunately, there’s relief in sight for cacao farmers and the consumers who depend on them. In 2010, scientists at the USDA’s Agricultural Research Service and universities partnered with IBM and the candy company Mars to sequence the genome of cacao, in order to help identify the markers of a more sustainable crop.

The cacao genome sequence has been released for free on the internet, where it can be accessed by researchers who can use it to improve cacao breeding techniques. Farmers can also use the cacao database to select the breeds that will flourish best under changing local conditions. And that’s sweet news for the future of one of the world’s favorite treats.