Stern Magazine (May 15, 1996)
Chemical Messengers of Love
We have been familiar with them longer in animals. Now we know that
human behavior too is guided by barely perceptible substances.
Scientists are constantly finding new evidence that these
pheromones, which are produced in the skin and are mostly
without scent, are decisive when it comes to desire and
love, appeal and sex.
Napoleon Bonaparte was to the point: "Don't wash any longer, I'm
coming back soon," he wrote in a dispatch from his camp to Empress
Josephine. The brilliant strategist obviously possessed an
infallible sense of how the nose plays a key role in love and
sex. Now, 200 years later, researchers can scientifically
explain the behavior of the little Corsican. The organ of
smell detects not only intoxicating perfume or the offensive
stench of a body. It can also register the mysterious agents
of enticement and information, the pheromones.
For humans they
guide many emotions, as well as sexual attraction and the choice
Although they are mostly odorless and waft through
the air only in the smallest traces, they determine who appeals
to us and who doesn't. Like invisible procurers, they stand behind
love at first sight, which strictly speaking, has to be called "love
at first smell."
These chemical messengers have also been discovered
in the last few years to play a role in the proverbial "spring fever."
Their great time comes when winter is over, the coat and cap are put
into mothballs, and colds no longer stop up the nose. Without
hindrance, these secret seducers can now escape from low-cut
necklines. They begin to show their full effect when they float
into a "foreign" nostril and land there on the "vomeronasal" organ.
This sensory instrument is only a centimeter long and as thin as a
match. Although it was described by a Dutch military doctor in the
eighteenth century, research only re-discovered it a short while ago.
Professor Werner Langthaler, psychologist at the University of Munster:
"It is a sensation that now, almost in the year 2000, we are tracking
down a new human sense." (See box on page 26.)
Without the VNO, the current abbreviation for the tongue twister,
nothing happens in the animal kingdom. Baby marmosets and grass carps,
blue crabs and ants release pheromones to mark the boundaries of their
territory, as a warning to enemies, as recognition signs, enticements to
love, status symbols, and for many other purposes. Queen bees use
pheromones to inhibit the sexual maturity of female workers and to make
the drones swarm. While entire brigades of researchers are focusing on
animal pheromones, little has been known until today about the chemical
agents of human attraction. We don't even know how they are produced.
There is every indication, however, that it happens in the skin, the
largest and most complex organ of the human body, an organ that still
presents scientists many mysteries. Crowded together in a single square
centimeter are on the average over six million cells, 5000 sensory
bodies, 100 sweat and 15 sebaceous glands, as well as 200 pain points,
10 to 25 pressure points, 12 cold and 2 war m points. Four meters of
nerve fibers and one meter of blood vessels guarantee interconnection
and supply. The most important pheromone factories are the armpits.
Their sweat glands mix together a series of attraction agents. The
substances are secreted during perspiration and evaporated from the
But what is actually attractive about them? And what do they have to do
with love and sex? Sweat glands in the armpit area are only active
during the times in which the human being is capable of reproduction.
They first take up their work in puberty and suspend it in menopause.
Not without good reason does the woman's head and therefore her nose
during snuggling lie mostly in the immediate vicinity of the man's
armpit. "For the transmission of pheromones, physical contact is
indispensable," asserts Charles Wysocki, professor of anatomy and
renowned researcher at the University of Philadelphia. "The smelling
radius and range of pheromones amounts at the most to a few
centimeters." Thick clothing, therefore, blocks these fleeting
messengers of love that, like a fine veil of scent on our skin, are
lying like a spring haze above a meadow of flowers. Frequent washing
thins the pheromones or dissipates them altogether. That was exactly
what Napoleon wanted to prevent.
"Full to the brim with pheromones" is the way neurophysiologist Luis
Monti-Bloch from the University of Utah in Salt Lake City described the
nasal groove running from the outer rim of the nostrils to the corners
of the mouth. And it is exactly there that someone who is affectionate
sticks the end of his nose when kissing. Professor Monti-Bloch: "The
kiss is probably a ritual that serves especially to detect pheromones."
That is "entirely obvious" in the gallant hand kiss.
For the psychologist Winnifred Cutler from Haverford near Philadelphia,
the act of love is an absolute bath in pheromones.
The researcher has determined that women who sleep with a man at least once a week have a
more regular period than those who are abstinent.
For this effect, however, neither man nor sex is responsible, but rather
the aura of male scent. Women on whom Cutler dabbed an alcoholic
extract of male armpit sweat under the nose each day for several weeks
also developed a regular cycle without any male visit or touching.
Quite specialized chemical agents of attraction seem to pour out of the
sexual organs. "The tip of the rat penis produces its own pheromone,"
says Clive Jennings-White of the University of Utah in Salt Lake City.
"Why should it be different for human beings?" Up till now, 35
different pheromones have been discovered in the rat. "I hardly believe
that we human beings possess fewer."
In five years of detective work, the researcher has uncovered 25
different chemical messengers in Homo Sapiens and decoded their
chemistry. Substances that excite sexual desire were also present.
"But we're not speaking about them!" says David Berliner. The 66-year
old, formerly a professor of anatomy at the University of Utah, heads
the pheromone companies "Pherin" and "Realm" in California. The experts
Jennings-White and Monti-Bloch are also conducting research at Pherin.
"What we are discovering," says Berliner, "we will only market as
medicines for impotence or disorder of the sexual drive, but in no case
as an aphrodisiac."
Anyway, one should not expect that, under the influence of such
substances, human beings would fall upon one another like male moths
upon a piece of blotting paper soaked in female attraction agents.
A main reason is that, besides aphrodisiacs, the spectrum of pheromones
contains substances that make one offensive. If you cannot get
someone's scent, then repelling pheromones and a natural defense
mechanism are at work. German researchers, like the American ones, have
proved that a person instinctively rejects people whose immune genes are
very similar to his own. In that way, nature intends not only to
prevent incest but also to exclude the possibility that descendants
result whose immune defense betrays dangerous gaps.
This mechanism works infallibly. Although the pheromone production is
dependent upon mood, health, and age, each human being possesses his own
distinctive pheromone aura. Search dogs obviously make use of this
"chemical i.d." when tracking down lost persons, just as infants do when
looking for their mother's nipple. By the second day of life they can
recognize the right source of milk by its scent, that is, by its
pheromones. Steered by the vomeronasal organ, traces of pheromones
guide the baby to its goal.
According to the opinion of Luis Monti-Bloch, the human VNO is as
powerful as that of a dog or cat. The professor: "Our VNO is about a
thousand times more sensitive than our sense of smell." By means of the
VNO, these chemical attractors have an effect upon the hypothalamus.
That is a region of the midbrain that regulates the most important
processes in the organism - body warmth, sexual drive, fat metabolism,
sleep, blood pressure, and breathing. In tests up to now, the
substances have influenced twenty various metabolic processes - within
fractions of a second.
The discovery of the human pheromones and their sensory organ is a scientific detective story
full of accidents, fortunate connections, and persistent detective work.
It begins in the year 1960. As a young professor of anatomy, David
Berliner had set his mind to find out which chemicals are in the skin.
In the University Hospital of Salt Lake City, he scratched skin cells
from the discarded plaster casts of skiers who had broken bones on the
steep mountains around the Mormon city. "We discard about 1000 cells an
hour per square centimeter. A lot could be found in the plaster casts."
He leached out the cells with solvents and let the extracts stand in
open bottles in the laboratory. "I never dreamed that the stuff could
To general amazement, the usual discord and hectic pace in the
laboratory was suddenly replaced by peace and quiet. A previously
unimaginable harmony even went so far that, after a common lunch, the
researchers played bridge. When Berliner closed up the bottles with the
skin extract, however, the collegiality evaporated. "From that hour on,
no one spoke of bridge!" The supposition that the unknown chemical
mixture had anything to do with the change of mood appeared entirely
erroneous to Berliner at the time.
In the middle of the 80's, the electron microscope researcher David
Moran of the University of Colorado in Denver discovered his interest in
the fine structure of the nasal network. The head of the Neck, Nose,
and Throat Department, Professor Bruce Jafek, with whom he worked,
mentioned in passing that one of his students was focusing on the fetal
VNO. Moran and Jafek asked one another whether the organ actually
atrophied, as it stated - poorly attested - in most of the texts. They
immediately put it to the test. They searched with the microscope and a
lot of light and found the VNO on each of their more than 200 patients.
The size of the VNO's opening in the nasal mucous membrane varies
between two millimeters and 0.2 mm, a size no longer perceivable with
the naked eye. From this little dimple, a passage a few millimeters
long extends into the organ, which is conical like an ice cream cone.
In the beginning of 1990, Berliner remembered his skin cell extract that
been frozen for a quarter of a century. He had followed attentively all
publications about VNO and pheromones. Now he wanted to know whether
his substances had an effect on this organ and turned to Monti-Bloch.
He, at first, was thoroughly skeptical; but then he developed an
apparatus that was supposed to measure electrical impulses created by
stimuli in the VNO and to record them through the computer as a kind of
VNO-EKG. A silver electrode as fine as a hair leads directly into the
opening of the VNO. It is surrounded by a casing through which a
pheromone-air mixture can be directed into the organ.
Monti-Bloch tested the apparatus on the olfactory mucus membrane, which
lies in the nose about five centimeters over the VNO. When he seasoned
the stream of air with scents, the apparatus showed a reaction. The
VNO, on the contrary, did not show the slightest electronic response,
even with the strongest scents. Only Berliner's skin extracts awakened
it to life.
For five years now, research at the companies founded by Berliner in
California have been running at top speed. Especially when the
researchers test the effects of newly discovered chemical messengers,
they experience surprises. With one substance, instead of becoming
love-crazed like tom-cats who scent a female in heat, one group of
subjects showed deep relaxation. In surprise, Monti-Bloch recorded that
the heartbeat and breathing of the test subjects slowed down and their
muscles relaxed. "With human beings, pheromones have other tasks than
to stimulate us to have sex," says Berliner. "Social pheromones," that
improve interpersonal relationships, are however "a gift of heaven."
Clive Jennings-White has already produced more than 100 artificial
pheromones. He calls them vomeropherins. They often have a stronger
effect than the natural substances. The chemist: "The potential is
gigantic! That's the reason we're having them patented like crazy."
Berliner: "I am certain that this research will open to us unbelievable
possibilities for treating illnesses." Artificial pheromones can be
employed as appetite suppressants, contraceptives, and sedatives. They
first thing they want to do however is to develop a remedy for prostate
cancer. The foundation for it is supposed to be a vomeropherin that
stops testosterone production in the bodies of sick persons. If the
amount of sexual hormone in the blood sinks, the cancer shrinks. Side
effects should not be expected, since the patient does not have to be
pumped full of drugs and hormones, but rather only has to "smell" the
Up to now, Berliner has put five million dollars into the research. He
earns his necessary small change with his perfume creation "Realm." The
cologne is supplied with two artificial human pheromones and is supposed
to produce a mild euphoria for the wearer and thus make it possible to
flirt with the opposite sex without nervousness or stress. The essence,
as a men's or women's version in the trade, seems to sell best. The
Wall Street Journal reported at the end of 1995 that Realm has become a
"surprise hit" at Bloomingdale's. The head of Pherin reproaches the
dozen or so competitors in the international market as "pig pheromones."
And he is right: According to their contents, most of the toilet waters
are mixed with androstenon, a boar pheromone that has no effect on
"There is no question that we all possess a vomeronasal organ," says
Professor Hans Hatt, cell physiologist at the University of Bochum. Any
throat, neck, and ears doctor who looks carefully can see it."
It was discovered in the year 1703 by a Dutch military doctor on a
soldier with a facial wound. Most anatomy textbooks, however, grant a
vomeronasal organ only to the embryo in the mother's womb. "We
disproved this nonsense years ago," says Professor Luis Monti-Bloch,
neurophysiologist at the University of Utah in Salt Lake City. "Every
healthy human has a VNO in each nostril. The organ is also fully
functional in the adult and connected by nerve paths to the brain.
Monti-Bloch could also prove that little researched agents of chemical
attraction, so-called pheromones, influence - among other things - the
heartbeat, breathing, skin temperature, and hormonal balance. The
pheromone researcher Clive Jennings-White sees the VNO as "our most
undervalued organ." For this chemist, active like Monti-Bloch at the
University in Salt Lake City, we are "pheromone animals." "Not for
nothing do we have a larger VNO than the horse."
David Berliner, one of the discovers of this secret seducer, classifies
the VNO as "our third most important sense." "It comes directly after
seeing and hearing - and before touch and smelling. Chemical
communication plays a key role also for us humans."
The VNO reacts as quick as lightning to any breath of a pheromone.
Physiological changes are already measurable after a ten-thousandth of a
second. Monti-Bloch: "This is proof that nerve paths from the VNO lead
directly to the brain; for only they could cause such a quick reaction."
Professor of Psychology Werner Langthaler of the University of Munster
confirms that: Monti-Bloch has clearly "proved that the VNO is
connected via stimulant pathways to the brain." The small detector of
chemical attraction agents in our nose is so sensitive that many highly
modern analysis apparatuses have had to exert themselves to keep up with
it. The VNO of persons examined by Monti-Bloch respond to 30 picograms
of pheromone - that is, thirty millionths of a billionth of a