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Be My Scientific Valentine
  1. A day for lovers

2. Chocolate 'n your heart

3. Canadian Diamonds

4. Bird mating: She rules!




single piece of chocolate





Precious things can grow on trees! Here's the pod of the cocoa tree.

















Five to six million farmers in South America, Africa and Asia make their living growing cacao trees. The average Americans eat 12 pounds of chocolate annually.











Too much cholesterol can injure arteries, especially those that supply the heart. Atherosclerosis is an accumulation of cholesterol-laden "plaque" in vessel linings.


  Chocoholic question
open box of heart-shaped box of chocolatesIn the best of all possible worlds, your sins would be good for you. You'd eat greasy fries and get thin. You'd watch basketball on TV, and your aerobic capacity would match Kobe Bryant's. You'd gobble the chocolate gift of your Valentine, and it would ward off heart attacks.

Now comes a study indicating that the blessed bean may indeed reduce the oxidation of "bad" cholesterol, called LDL -- low-density lipoprotein. Oxidation helps LDL glom onto arteries, helping initiate atherosclerosis -- hardening of the arteries -- that can cause heart attack or stroke.

Chocolate, like many plant foods, contains antioxidants -- molecules that disarm free radicals, reactive molecules that damage and age tissue.

 Large yellow pod split in half with cocoa beans inside.Before we even start the engine on this research, however, let's drive past the conclusion: the effect was quite limited. And chocolate will only help as part of a balanced diet that stresses basic nutrition, says Penny Kris-Etherton, professor of nutrition at Penn State. "You can't get all your antioxidants just from chocolate," she says. "Maybe a little bit of chocolate can be part of an antioxidant cocktail which is comprised mainly of fruits and vegetables, and whole grains."

And that's not the word of a detractor -- that's the word from the lead researcher! (We Why Filers are immediately dreaming up scanty whole-wheat wafers, drenched in chocolate, with a raspberry-chocolate sauce...)

As you might have guessed, Kris-Etherton's research was funded in part by the American Cocoa Research Institute, an industry group that gets money from Hershey and similar choco-bizzes.

Needed. A few good volunteers
To check how chocolate affects blood chemistry, Kris-Etherton rounded up 23 volunteers (which was no particular challenge, she told us) and fed them either a standard American diet, or a diet that included 22 grams of cocoa and 16 grams of dark chocolate (per day, not just on Valentine's!). After four weeks, she had the subjects cool out for two weeks, then swapped their diets (see "Effect of Cocoa..." in the bibliography).

No word on whether she allowed subjects to receive Valentine's cards... Then she tested blood and found that the LDL cholesterol oxidized more slowly in the blood of the choco-gobblers.

Chocolate growers surround large pile of fresh cocoa beans.Unfortunately, the so-called "oxidative lag time" was only 8 percent longer.

That's not a lot, and even Kris-Etherton admits it might mean nothing in the real world. "We don't know if it has significance, it's a small change, but it would suggest that the LDL particles are protected" from oxidative degradation by eating chocolate.

A noisy debate
In any case, the research must be seen as part of a long debate over the dietary role of antioxidants. A few years back, antioxidants (think vitamins A, C and E) were considered magic bullets in the battle against aging. They would halt oxidative damage, and we would live forever -- almost.

But after some large experiments failed to prove this notion, the antioxidant story is rather murky. Antioxidant research is gnarly because plant foods contain thousands of antioxidants in myriad combinations and concentrations, and it's fiendishly tough to pin down the exact role of individual antioxidants like the flavonoids in chocolate.

Although, as Kris-Etherton says, "There is some good evidence to show that high fruit and vegetable intake protects against heart disease and cancer," isolating a single factor is difficult. "Maybe it's the whole milieu that's synergistic. Drawings show progressive cholesterol and plaque buildup in artery.There are a lot of things in fruit and vegetables, including antioxidants, that are helpful." If that's not confusing enough, let's say you wanted to get your antioxidants from chocolate. But both the dark and milk varieties contain antioxidants, with the level depending on the variety of the cocoa bean and how it was processed.

And no, a high price does not guarantee a high level of antioxidants, says Kris-Etherton.

On the brighter side, perhaps that's simply an argument for eating a balanced diet containing both dark and milk chocolate, in both expensive and el-cheapo forms.

If chocolate is too healthy for your Valentine, may we suggest diamonds?




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