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In Search of the Healing Power of Chocolate

Mars chemist Harold Schmitz holds a chemical model of a flavanol. These compounds give chocolate its taste and might also provide some healthful benefits, such as lowering blood pressure.
Joanne Silberner, NPR
Mars chemist Harold Schmitz holds a chemical model of a flavanol. These compounds give chocolate its taste and might also provide some healthful benefits, such as lowering blood pressure.

At a Mars factory in Elizabethtown, Pa., an assembly line moves millions of pieces of Dove dark chocolate.

The factory's secret -- and it's a proprietary secret -- is a method of processing chocolate that maintains something called flavanols, a class of chemicals found in raw cocoa beans, red wine and green tea.

It's all about roasting the beans for the right amount of time, and at the right temperature. "It's a much gentler process," says plant manager Bob Harvey. "You can destroy the flavanols if you don't know what you're doing."

Mars makes two products high in flavanol, Dove dark chocolate and CocoaVia. The latter has a soybean-based ingredient known to lower cholesterol.

More than 20 years ago, Mars scientists were trying to figure out what gives chocolate its flavor. Mars chemist Harold Schmitz says they focused on flavanols. And then they started to understand that flavanols might have more to offer than just taste.

"As we started to understand the chemistry of these molecules," Schmitz explains, "we realized they could have biological attributes not just related to the tongue and flavor, but to other parts of the body in the context of health."

Harvard scientist Norman Hollenberg discovered that natives on an island off Panama had low blood pressure when drinking their favorite drink made from cocoa that had been minimally processed. Together Mars and Hollenberg determined that the key factor was flavanols.

So Mars has been working for years to figure out how to manufacture chocolate high in flavanols. Schmitz says starting with the right kind of cocoa pod is key.

He compares a football-sized, red, yellow and black pod to a rounder, yellow pod about half the size to show how much pods can differ from one another. Genetics is one of the key factors for the difference. And genetics can lead to greatly differing flavanol levels.

Schmitz says Mars has spent many years and a lot of money figuring out the right genetics and growing conditions that will lead to maximum levels of flavanols.

So at the Elizabethtown plant, manager Bob Harvey is very careful. He knows a mistake in processing can destroy flavanols.

But he won't give details about the manufacturing process, or say how high the flavanol levels are in the finished chocolate. He will say that he loves the end result; he eats a half dozen Dove dark chocolates a day.

Mars and Harvard's Hollenberg have shown flavanols increase blood flow, but they haven't yet proven their chocolate lowers blood pressure and heart attack risk.

There are those who doubt the magic of Dove chocolate and CocoaVia.

Alice Lichtenstein won't comment on the Mars products specifically. She's a nutrition professor at Tufts University. She will talk about what concerns her with any "healthy" chocolate. It's the calories. CocoaVia bars are 90 calories apiece. A serving of Dove dark has 190 calories. "About two-thirds of Americans are overweight or obese," says Lichtenstein, "and the last thing that we want to do is actually add food and extra calories to the diet on a daily basis."

Lichtenstein won't rule out the possibility that flavanols may prove to be helpful. But if that happens, she says, calorie-free pills would be a better option.

Mars chemist Schmitz counters that people are more likely to eat candy bars than take pills.

Dove chocolate is available across the United States, but CocoaVia is in more limited distribution, at some Wal-Marts, Targets and Walgreens, and online. How well the products are selling is a mystery. Mars is a family owned company and doesn't have to tell.

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Joanne Silberner is a health policy correspondent for National Public Radio. She covers medicine, health reform, and changes in the health care marketplace.