researchers have tried to get to the bottom of our love affair with chocolate.

Biologically active compounds are encased in each chocolatey morsel,

leaving scientists to wonder if there’s a physiological basis for our cravings.

We know that chocolate includes stimulants like caffeine and theobromine.

Also, there’s tryptophan and phenylethylame,

neurotransmitters associated with pleasure.

And don’t forget anandamide,

a compound in the same family as THC,

the active ingredient in marijuana.

It has fueled speculation that chocolate is addictive.

With so many feel-good chemicals in every bite,

it could seem likely our hankering is purely physiological.

But scientists say probably not.

In a study from the 1990s,

volunteers were given chocolate-- or a pill with almost all the active compounds.

The pill alone did not satisfy.

White chocolate, however, did satisfy.

It’s made from the fat of chocolate and has the same calorie load and sweetness,

but lacks most of the most pharmacological ingredients better than milk or dark chocolate.

But we can’t say that white and milk chocolate both satisfied because of the sugar alone,

because in general, other sweets don’t satiate those cravings.

Then there’s anandamide,

which was NOT studied in the pill experiment.

But it's fat soluble.

So it could have been present in both the white and milk chocolate,

explaining some of our cravings.

But there’s not enough in chocolate to achieve a noticeable “high.”

Current calculations suggest a 70-kg person

would need to eat almost a third of his weight, 25kg, in order to feel much of anything.

And what about the fact that women reach for chocolate more often than men,

especially around monthly menstruation?

That could be culturally mediated.

Scientists say that our cocoa desires are more about coping with stress

in a culturally accepted--and delicious way-- than anything else.

For now, the scientific consensus

is that chocolate craving is more about the riot of pleasure for our senses.

From its melt-in-your mouth taste to its sweet aroma and perfect fragrantness.

For Scientific American’s Instant Egghead.

I’m Dina Fine Maron.