Scientific Proof

Scientific Proof That Pheromones Play A Key Role In Human Attraction and Sexual Arousal

Nexus Pheromones™ has been formulated with extensive reference to over 12 years worth of scientific studies in the field of human sex pheromones.

Here’s just a small sampling of the studies that demonstrate the role of pheromones in human sexual behavior, mating, and attraction: 

Excerpts From Scientific Journals & Studies

Evidence that androstadienone, a putative human chemosignal, modulates women’s attributions of men’s attractiveness – Eur J Obstet Gynecol Reprod Biol. 2005 Feb 1;118(2):135-42.

Quote: “Men were rated more attractive when assessed by women who had been exposed to androstadienone, an effect that was seen in two out of three studies. The results suggest that androstadienone can influence women’s attraction to men, and also that research into the modulatory effects of androstadienone should be made within ecologically valid contexts.”

Human pheromones and sexual attraction – Neuro Endocrinol Lett. 2001 Oct;22(5):309-21. 

Quote: “Several studies indicate that humans indeed seem to use olfactory communication and are even able to produce and perceive certain pheromones; recent studies have found that pheromones may play an important role in the behavioural and reproduction biology of humans. In this article we review the present evidence of the effect of human pheromones and discuss the role of olfactory cues in human sexual behaviour.”

Behavioral and electrophysiological effects of androstadienone, a human pheromone – Bernard I. Grossera, Louis Monti-Blocha, b, Clive Jennings-Whiteb and David L. Berliner

Quote: “Forty normal female subjects were randomized in a double-blind manner to receive either control or 100 pg of androstadienone directly to the vomeronasal organ. We report that administration of this steroid under these conditions results in a significant reduction of nervousness, tension and other negative feeling states. Concordant changes were observed in autonomic physiology.

The Scent of Symmetry: A Human Sex Pheromone that Signals Fitness – Randy Thornhilla , Steven W Gangestadb 

Quote: “In both sexes, facial attractiveness (as judged from photos) appears to predict body scent attractiveness to the opposite sex. Women’s preference for the scent associated with men’s facial attractiveness is greatest when their fertility is highest across the menstrual cycle. The results overall suggest that women have an evolved preference for sires with good genes.

The scent of a woman – Horm Behav. 2008 Nov;54(5):597-601. Epub 2008 Jun 14.

Quote: “Recent work has demonstrated that exposure to nonodorous testosterone and estrogen derivatives can activate specific human brain regions and induce sexual effects. These effects seem to be sex-specific: Testosterone derivatives affect women, and estrogen derivatives affect men.”

Human pheromones: integrating neuroendocrinology and ethology – Kohl JV, Atzmueller M, Fink B, Grammer K

Quote: “The effect of sensory input on hormones is essential to any explanation of mammalian behavior, including aspects of physical attraction. The chemical signals we send have direct and developmental effects on hormone levels in other people. Since we don’t know either if, or how, visual cues might have direct and developmental effects on hormone levels in other people, the biological basis for the development of visually perceived human physical attraction is currently somewhat questionable. In contrast, the biological basis for the development of physical attraction based on chemical signals is well detailed.

Male Axillary Extracts Contain Pheromones that Affect Pulsatile Secretion of Luteinizing Hormone and Mood in Women Recipients – Biology of Reproduction June 1, 2003 vol. 68 no. 6 2107-2113

Quote: “Human underarm secretions, when applied to women recipients, alter the length and timing of the menstrual cycle. These effects are thought to arise from exposure to primer pheromones that are produced in the underarm. Pheromones can affect endocrine (primer) or behavioral (releaser) responses, provide information (signaler), or perhaps even modify emotion or mood (modulator). In this study, we extracted underarm secretions from pads worn by men and placed the extract under the nose of women volunteers while monitoring serum LH and emotion/mood. Pulses of LH are excellent indicators of the release of GnRH from the brain’s hypothalamus. In women, the positive influence of GnRH on LH affects the length and timing of the menstrual cycle, which, in turn, affects fertility. Here we show that extracts of male axillary secretions have a direct effect upon LH-pulsing and mood of women. In our subjects, the putative male pheromone(s) advanced the onset of the next peak of LH after its application, reduced tension, and increased relaxation. These results demonstrate that male axillary secretions contain one or more constituents that act as primer and modulator pheromones.

Encoding Human Sexual Chemosensory Cues in the Orbitofrontal and Fusiform Cortices – Journal of Neuroscience, 2008, 28:11416

Quote: “Here, we use functional magnetic resonance imaging to show that the right orbitofrontal cortex, right fusiform cortex, and right hypothalamus respond to airborne natural human sexual sweat, indicating that this particular chemosensory compound is encoded holistically in the brain. Our findings provide neural evidence that socioemotional meanings, including the sexual ones, are conveyed in the human sweat.

Sex and the Nose: Human Pheromonal Responses – Journal of the Royal Society of Medicine 2007 100:268-274

Quote: “Species also release chemical signals into the environment to communicate their presence and to evoke behavioural responses in other members of their species – usually concerned with mating responses. The term ‘pheromone’ was first coined in the 1950s for a substance secreted by an animal that causes a specific reaction in another animal. The actions and mechanisms of pheromones have been widely studied in animals and with recent advances in molecular and cell biology the scope and importance of olfactory communication is only just being realized. Pheromone communication is known to exist in almost all social animals.”

Smelling a Single Component of Male Sweat Alters Levels of Cortisol in Women – Journal of Neuroscience, February 2007 27(6):1261-1265

Quote: “We found that merely smelling androstadienone maintained significantly higher levels of the hormone cortisol in women. These results suggest that, like rodents, humans can influence the hormonal balance of conspecifics through chemosignals. Critically, this study identified a single component of sweat, androstadienone, as capable of exerting such influence.”

Sniffing human sex-steroid derived compounds modulates mood, memory and autonomic nervous system function in specific behavioral contexts – Behavioral Brain Research, June 2004 152(1):11-22

Quote: “These results suggest that sex-steroidal compounds modulate mood, memory and autonomic nervous system responses and increase their significance within specific behavioral contexts. These findings lend support to a specific role for these compounds in chemical communication between humans.”

Male Axillary Extracts Contain Pheromones that Affect Pulsatile Secretion of Luteinizing Hormone and Mood in Women Recipients – Biology of Reproduction, June 2003, 68:62107-2113

Quote: “In this study, we extracted underarm secretions from pads worn by men and placed the extract under the nose of women volunteers while monitoring serum LH and emotion/mood… Women reported experiencing less tension and being more relaxed during exposure to the male extract, suggesting the presence of a modulator pheromone. These effects may serve as objective measures of primer and modulator pheromone activity that could guide an analytical isolation of the active axillary constituents.”

Psychological State and Mood Effects of Steroidal Chemosignals in Women and Men – Hormonal Behavior, 2000 Feb: 37(1):57-78

Quote: “We tested the hypothesis that isolated steroids, claimed to act like pheromones, affect human psychological state or mood. In the first experiment, we established that two steroids, Delta4, 16-androstadien-3-one and 1,3,5(10)16-estratetraen-3-ol, modulated emotional states within 6 min of exposure. In men and women, neither steroid had specific effects on states of alertness or negative-confused mood. However, both steroids increased positive stimulated mood state in women but decreased it in men. In a second experiment on women, we replicated that Delta4,16-androstadien-3-one modulated their general mood state, even when women were not aware of its odor and gave identical olfactory descriptions for the steroid and the control carrier solutions. In this within-subjects, repeated-measures experiment, androstadienone prevented the deterioration in general mood which occurred during exposure to the clove oil carrier solution in the laboratory environment. Thus, androstadienone appears to modulate affect, rather than releasing stereotyped behaviors or emotions.

Human Olfactory Communication of Emotion – Perception and Motor Skills, 2000, 91:771-781

Quote: “Nonhuman animals communicate their emotional states through changes in body odor. The study reported here suggests that this may be the same for humans. We collected underarm odors on gauze pads from 25 young women and men on two different occasions. On one occasion the donors mere induced to feel happy by viewing an excerpt from a funny movie whereas on the other, separated by a day, they were induced to feel afraid by watching an excerpt from a frightening movie. One week later, 40 women and 37 men were asked to smell several different bottles, some of which contained underarm odor pads collected during the happy movie, some contained underarm odor pads collected during the frightening movie, whereas others contained unused pads (control odor). Each odor was identified on two separate tasks that involved identifying the odor from among three odors and identifying it again from among six odors. Data were the number of women and men who identified an odor correctly on both tasks. When asked to select which bottles contained “the odor of people when they are happy,” women chose the correct bottles for both tasks significantly more often than chance. Men chose the bottle which contained the body odors collected when women (but not men) viewed the happy movie more often than would be expected by chance. When asked to select which bottles contained “the odor of people when they are afraid,” women and men both chose the bottle that contained the body odors collected when men (but not women) viewed the frightening movie more often than would be expected by chance. The finding suggests that there is information in human body odors indicative of emotional state. This finding introduces new complexity in how humans perceive and interact.”

Olfaction in Humans with Special Reference to Odorous 16-Androstenes: Their Occurrence, Perception and Possible Social, Psychological and Sexual Impact – Journal of Endocrinology 1993 137:167-187

Quote: An earlier experiment than this (Kirk-Smith & Booth, 1980) had indicated that the odour of androstenone had important effects on choice of seating by men and women in the presence of other people. In this study, a chair in a waiting room of the Birmingham University Dental Health Centre was sprayed with 3-2, 16 or 32 pg 5a-androstenone at different times. On a day when the position of the sprayed chair was to be changed, it was washed with detergent and exchanged with a distant unodorized chair. A total of 840 people were observed, and a rota of receptionists (who were unaware of the true purpose of the experiment) noted the position and sex of the patients on a blank seating plan. Observations were taken at 30-min intervals during 4 days at each of the three levels of 5a-androstenone sprayed. The results indicated that significantly more women used the odorized seat when it bore 3-2 or 32 pg of steroid, with fewer men using it at the 32 pg level. The authors suggested that the women might have been attracted to the low concentrations used at probably a subliminal level because of the experience of its association with men.

Effect of Putative Pheromones on the Electrical Activity of the Human Vomeronasal – Organ and Olfactory Epithelium, October 1991 4:573-582

Quote: “The summated receptor potential was recorded from the vomeronasal organ (VNO) and olfactory epithelium (OE) of 49 human subjects of both sexes (18 to 55 years old) using surface non-polarizable silver-silver chloride electrodes. 15-25 pg of human putative pheromones, clove oil and a diluent were administered to the VNO or the OE in 0.3-1 s pulses from a 0.05 mm dia cannula connected to a multichannel delivery system. Local stimulation of the VNO produces negative potentials of 1.8-11.6 mV showing adaptation. Responses are not obtained when the recording electrode is placed in the nasal respiratory mucosa. Pheromone ER-830 significantly stimulates the male VNO (P < 0.01; n = 20), while ER-670 produces a significant effect on female subjects (P < 0.001; n = 20). The other pheromones tested do not show significantly different effects in both male and female (P > 0.1). Similar quantities of odorant or diluent produce an insignificant effect on the VNO. Stimulation of the OE with clove oil produces depolarization of 12.3 +/- 3.9 mV, while pheromones do not show a significant effect. Our results show that the VNO is a functional organ in adult humans having receptor sites for human putative pheromones.”

Articles From Popular Media Sources

Love Is All in Your Head – Or Is It in Your Genes? – Laurie Barclay, MD WebMD Health News

Quote: “A 1998 study from the Athena Institute for Women’s Wellness Research in Chester Springs, Pa., documented the sexual activity of 38 young to middle-aged heterosexual men while using pheromones. Users of pheromones, but not of an inactive control substance, had increased frequency of informal dates, affectionate gestures, sleeping next to a romantic partner, foreplay, and sexual intercourse.”

Study Finds Proof That Humans React To Pheromones – Melinda Wenner

Quote: “Women can smell a man’s intentions When a guy is aroused, his sweat activates the female brain, study reveals.”

Sexual Orientation: In The Brain Study Finds Brain Differences In Reaction To Testosterone Scent – Christine Lagorio

Quote: “They found that gay men differed from heterosexual men and women and from lesbian women, both in terms of which body odors gay men preferred and how their own body odors were regarded by the other groups.”

Male sweat boosts women’s hormone levels – Robert Sanders

Quote: “Just a few whiffs of a chemical found in male sweat is enough to raise levels of cortisol, a hormone commonly associated with alertness or stress, in heterosexual women, according to a new study by University of California, Berkeley, scientists. The study, reported this week in The Journal of Neuroscience, provides the first direct evidence that humans, like rats, moths and butterflies, secrete a scent that affects the physiology of the opposite sex. “This is the first time anyone has demonstrated that a change in women’s hormonal levels is induced by sniffing an identified compound of male sweat,” as opposed to applying a chemical to the upper lip, said study leader Claire Wyart, a post-doctoral fellow at UC Berkeley. The team’s work was inspired by previous studies by Wyart’s colleague Noam Sobel, associate professor of psychology at UC Berkeley and director of the Berkeley Olfactory Research Program. He found that the chemical androstadienone – a compound found in male sweat and an additive in perfumes and colognes – changed mood, sexual arousal, physiological arousal and brain activation in women.”

Pheromones In Male Perspiration Reduce Women’s Tension, Alter Hormone Response – ScienceDaily (Mar. 17, 2003)

Quote: “Scientists at the University of Pennsylvania and the Monell Chemical Senses Center in Philadelphia have found that exposure to male perspiration has marked psychological and physiological effects on women: It can brighten women’s moods, reducing tension and increasing relaxation, and also has a direct effect on the release of luteinizing hormone, which affects the length and timing of the menstrual cycle. The results will be published in June in the journal Biology of Reproduction and currently appear on the journal’s Web site. “It has long been recognized that female pheromones can affect the menstrual cycles of other women,” said George Preti, a member of the Monell Center and adjunct professor of dermatology in Penn’s School of Medicine. “These findings are the first to document mood and neuroendocrine effects of male pheromones on females.”

Secrets of Human Attraction – BBC News: August 29, 2000

Quote: “A gene that could explain how humans pick up powerful chemical signals called pheromones may have been pinpointed for the first time. The discovery promises to give scientists a new understanding of our basic instincts. Pheromones are known to trigger physical responses including sexual arousal and defensive behaviour in many species of insects, fish and animals. There has long been speculation that humans may also use these chemicals to communicate instinctive urges. Women living together often synchronise their menstrual cycles because they secrete an odourless chemical in underarm sweat. But until now scientists have not been able to explain how and where in the body the chemicals are picked up and their messages passed to the brain. Many animals, including mice, rabbits and pigs, have a special organ called the vomeronasal organ (VNO). This relays chemical signals directly to the most primitive centres of the brain, stimulating instinctive reactions. In human embryos these organs exist but they appear to perform no function after birth. Now, scientists at Rockefeller University in New York and Yale University in Connecticut believe they have found a gene which may create pheromone receptors. A receptor is an area on a cell that binds to specific molecules. Called V1RL1, the gene resembles no other type of mammalian gene and bears a strong similarity to those thought to create pheromone receptors in rats and mice. “People have taken an anatomical approach to the issue in the past. This is the first attempt to look at the molecular biology,” said Dr Peter Mombaerts from Rockefeller University in the journal Nature Genetics.”

Pheromones: Potential Participants in Your Sex Life – CNN News: June 25, 1999

Quote: “Couples who are having sexual problems could use pheromones combined with traditional therapy to enhance desire. It’s also possible, some researchers say, that pheromones could be a mood enhancer, alleviating depression and stress. And the most far-reaching hypothesis so far is that pheromone treatment could control prostate activity in men to reduce the risk of cancer. If you’re looking for the man or woman of your dreams, unsuspecting pheromones in your body scent are most likely playing a large and very clever role in mate attraction. According to an article in “Psychology Today,” how our body odors are perceived as pleasant and sexy to another person is a highly selective process. We usually smell best to a person whose genetically based immunity to disease differs most from our own. This could benefit you in the long run, making for stronger, healthier children.”

Study Finds Proof that Humans React to Pheromones – CNN News: March 11, 1998

Quote: “Though any number of animals and insects use pheromones to communicate with each other about important things such as food, territory and sex, the idea that humans might be similarly influenced has been controversial among scientists. But now, researchers at the University of Chicago say they have the first proof that humans produce and react to pheromones. … One enduring mystery of pheromones is that if they are undetectable by the human sense of smell, how can humans be influenced by them? The answer, some researchers believe, is that pheromones are detected by the same nerve cells in the nose used to detect odor or perhaps by another structure in the nose called the vomeronasal organ.”

Pheromones In Male Perspiration Reduce Women’s Tension, Alter Hormone Response – Science Daily: March 17, 2003

Quote: “Scientists at the University of Pennsylvania and the Monell Chemical Senses Center in Philadelphia have found that exposure to male perspiration has marked psychological and physiological effects on women: It can brighten women’s moods, reducing tension and increasing relaxation, and also has a direct effect on the release of luteinizing hormone, which affects the length and timing of the menstrual cycle. In a study led by Preti and colleague Charles J. Wysocki, extracts from the underarms of male volunteers were applied to the upper lip of 18 women ages 25 to 45. During the six hours of exposure to the compound, the women were asked to rate their mood using a fixed scale. “Much to our surprise, the women reported feeling less tense and more relaxed during exposure to the male extract,” said Wysocki, a member of the Monell Center and adjunct professor of animal biology in Penn’s School of Veterinary Medicine. “This suggests that there may be much more going on in social settings like singles bars than meets the eye.”