Lusty Appetites

By Robert L. Wolke
Wednesday, February 14, 2007

From the time of the ancient Greeks, foods have been used in seduction. Topping the list of purported aphrodisiacs, at one time or another, are edibles that sound mundane by today's standards: anise seed, avocados, basil, chili peppers, figs, garlic, ginger, honey, licorice, nutmeg, pine nuts, tomatoes. For the more simple-minded, any food that might be imagined to resemble part of the human anatomy has also been included on the list. Whether any of them work is questionable.

Of course, natural sources of attraction do exist in some animals. Many species attract mates via pheromones, chemicals discharged into the air by members of one sex and interpreted by the other as an invitation to mate. Pheromones are detected by a pair of tiny ducts in the nose called the vomeronasal organ, which is distinct from the receptors that detect ordinary smells.

But in humans, that organ appears to be either absent or insensitive, bred out of us some 23 million years ago, once we developed keen color perception and were able to see farther than we could smell. We could then spot likely mates visually, rather than chemically. (What other species wears makeup?) So despite the pitches for "pheromone"-containing after-shave lotions and sprays, there is no solid evidence supporting the existence of sexually stimulating pheromones in humans.

What about out-and-out aphrodisiacs in the form of drugs?

Alcohol and marijuana merely lessen inhibitions, thereby clearing the path toward what might well have happened anyway. Nor do Viagra and its imitators boost the libido; they merely assist the mechanics when the spirit is already willing but the flesh is weak. And forget Spanish fly, aspirin in Coke and all the other fantasies of adolescent boys.

So does anything work? To borrow from M.F.K. Fisher, consider the oyster. Slurping a supple, sopping, saporific oyster from its shell is one of the most sensuous of gastronomic pleasures, perhaps provoking thoughts of pleasures of another kind. In fact, the oyster has enjoyed such an enduring reputation as an aphrodisiac that scientists thought they had to come up with some validation for the idea. They came up with zinc. Zinc is essential for healthy sexual function, and oysters contain more zinc per serving than any other food. Therefore. . . .

Well, not so fast. It is possible that a person who is deficient in zinc and defective in sexual function might regain some functionality after consuming several dozen oysters. But for the normal person, zinc has not been shown to enhance sexuality.

And then there is chocolate, which -- it's a fact -- women crave more than men do. Chocolate is the prototypical love gift from a suitor, and with good reason. It contains phenylethylamine, a stimulant related to adrenaline that raises the heart rate, boosts blood pressure and heightens sensation. Chocolate also contains anandamide, a so-called cannabinoid that stimulates the same receptors as tetrahydrocannabinol, or THC, the active chemical in marijuana. Nevertheless, it is doubtful that the minute amounts of those chemicals in chocolate have any measurable effects.

Now for the good news. After centuries of dedicated research, chemists have finally synthesized a drug that appears to be a genuine aphrodisiac for both women and men. It is bremelanotide (formerly called PT-141), produced by Palatin Technologies Inc. in cahoots with King Pharmaceuticals Inc. Preliminary (Phase II) trials have produced definitely positive results. Advanced (Phase III) clinical trials are scheduled for early this year.

You can't get bremelanotide yet, despite the many bogus offers you'll find by Googling it. But in a couple of years, who knows? It might even come in heart-shaped boxes.

Robert L. Wolke can be reached

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