Ask the Doctors

Dear Doctor: I have read about the health benefits of dark chocolate for the brain and the heart, but that it must contain about 80 percent chocolate to be effective. How much sugar or additives (nuts, fruit) can be added before chocolate loses its health benefits?

Dear Reader: Ah, chocolate, a food that so often inspires a passionate response. The fact that it also offers a host of proven health benefits seems almost too good to be true.

A number of studies over the years have linked cocoa, the basic building block of chocolate, to cardiovascular benefits, cancer prevention, a lower risk of stroke, better blood flow to the brain, lower blood pressure and improved insulin metabolism. Cocoa also contains important minerals, including zinc, iron, magnesium and potassium.

With your question about the percentage of cocoa in a chocolate product, you've zeroed in on the vital detail. At what point does chocolate go from being just another kind of candy to becoming a beneficial food?

Let's start with a bit of background.

Chocolate is derived from cocoa beans, which are the seeds of the cacao tree, a small, shade-loving evergreen in the tropical regions of the Americas. These beans are high in a substance known as flavonols -- sometimes also referred to as flavonoids. Flavonols, which fall into the category of antioxidants, have anti-inflammatory properties.

The catch is that cocoa -- or pure chocolate -- is quite bitter. That means sweetening agents and milk solids are added to make it more palatable. Depending on the percentage of cocoa in any particular preparation, the result is a product that contains varying degrees of sugar and calories. And while cocoa has proven health benefits, sugar definitely does not.

When it comes to the health benefits of chocolate, the higher the percentage of cocoa content, the better. Sixty percent cocoa is widely considered the minimum when looking to a chocolate product for health benefits. But don't rely solely on the words "dark chocolate" when looking at the label.

In the U.S., a product with as little as 35 percent cocoa may be designated as dark chocolate. European chocolates set the bar a bit higher, with a minimum of 43 percent cocoa. And if you're one of those who love white chocolate, we're afraid there's some bad news. White chocolate is made from the fat of the cocoa bean and contains no actual cocoa at all.

And now, amid all this amazing chocolate news, a bit of a reality check.

A group of scientists from Harvard who reviewed the data from 24 studies pinpointing various health benefits associated with cocoa found that the average dose of flavonols ingested by the test subjects was 400 milligrams per day. Turns out, that's the equivalent of (are you sitting down?) eight bars of dark chocolate, or 30 bars of milk chocolate per day.

If you want to match that intake, cocoa supplements are available that skip the sweeteners and fillers that make chocolate so delicious. But if you're going to add actual chocolate to your diet, limit it to 2 ounces per day, and go with as high a percentage as you will actually enjoy.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

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