PHEROMONES: Do Humans Have Sexual Responses To Scent?

Author :- Health In Vitro Feb. 19, 2021, 9:24 a.m.
PHEROMONES: Do Humans Have Sexual Responses To Scent?

The wide distribution of products supposedly containing pheromones has been on the rise lately because of their seemingly magical effect in attracting love and sexual intent.

From pheromone oils, sprays and perfumes, and what-not; pheromones are the “hottest” things at the moment. Some big brand perfumes claim to have the perfect scent that ensnares the senses and attracts the opposite sex all day long.

This idea is often propagated in commercials and adverts. So, what are pheromones, and how do they work? Do they have acclaimed effects on humans? Let’s take a look.

What are pheromones?

A pheromone is a chemical released outside the body of an animal that influences the behavior or hormone system of another animal of the same species.

The term itself was coined by the German biochemist and swiss entomologist, Peter Karlsson and Martin Luscher in 1959.  Pheromone is a Greek word derivative that stands for “carrier of excitation”.The researchers discovered special molecules produced by certain animals and insects that were similar to hormones but produced outside the body to evoke changes in the behavior and physiology of other animals.

The first female pheromone-scent was also identified that same year in female silk moths and was referred to as bombykol. The chemical is secreted by female moths to attract their male counterparts, and it can cover long distances even in minute concentrations.

Types of pheromones

The four major types of pheromones are as follows :

Releasers: They trigger a specific and immediate behavioral response that is often associated with sexual stimulation. It is used by animals to woo or attract a mate. The pheromones produced by the female moth is a typical example.

Primers: Unlike releaser and primer pheromones do not trigger an immediate response. They cause changes to the hormonal and developmental system of another organism. They mostly interfere with reproductive functions such as pregnancy, menstrual cycle, and puberty.

They can contribute to the success or failure of these processes. When a female animal gets pregnant for another male that is not her mate, primer pheromones can detect this and cause spontaneous abortion of the fetus.

Signalers: They provide information signals. They help animals recognize the hierarchy to which they belong. It also tells an animal on the type of food consumed by other animals which signal the near proximity of available food.

They also help a mother recognize her offspring by scent. The Signalers provide genetic odor print which is as unique as fingerprints.

Modulators: These are mostly found in sweat and they can change or adjust bodily functions. They affect mood and a female’s menstrual cycle.

Pheromone functions in animals

The primary  functions of pheromone in animals are:

  • They help in mate selection
  • Defend animals against predators
  • Help animals overcome a host through mass attacks
  • Provide alarm signals to warn against the impending threat
  • Help organisms mark their territory to protect against invasion
  • Plays a role inbreeding.
  • Creates a bond between a mother and her offspring

Effects and functions of pheromones in humans

In many mammals, pheromones originate from the vomeronasal organ (VNO) found in the nose. The VNO has receptors for pheromones that cause hormone changes and prepares an animal for sexual activity. Pheromones are generally odorless, so the VNO does not pick smells or scents.

Humans do not have a VNO structure, or perhaps we do, but they are regarded as being dormant and ineffective, and this is why scientists have postulated that humans do not respond to pheromones. The only evidence of human pheromones is those found in a growing fetus that atrophies before birth.

However recent hypothesis suggests that pheromones are processed and detected in the olfactory bulbs found in the brain. Nevertheless, research on human pheromones has been widely conflicting.

A German doctor, Gustav Jager was the first to bring to light the human version of pheromones which he named anthropines. According to Jager, these anthropines are lipophilic compounds (dissolve in fats or lipids) associated with the skin follicles that gives humans a distinct odor.

After Jager’s findings, a psychologist called Martha McClintock claimed that women living together can synchronize their menstrual cycles due to the effects of pheromones. Martha and a colleague in 1998, conducted a study that showed that women can have similar changes in their menstrual cycle when exposed to each other’s body odor.

Martha’s study suggested that humans may have another system beyond the sense of smell that triggers the sexual response. However, a couple of studies refuted this claim and attributed it to mere chance.

After Martha’s experiment, various other studies and scientists emerged with claims of pheromones existing in humans. Pheromones have been linked to the mammary glands of lactating mothers based on the fact that babies can detect the distinct scent of their mother’s breast, but again there is no solid evidence to support this claim and some experts believe that babies simply act on the prior knowledge of their mother’s distinctive scent.

Another study claimed that women can sense a man’s sexual intentions, the study which was published in 2016, found a substance called progesterone derivative 4,16-androstadien-3-one(AND), that causes swelling in the erectile tissues of the female nose.

The claim that AND could be a human pheromone was refuted by a study published in March 2017 where participants of the study were exposed to the chemical and asked to evaluate attractiveness and gender perception in pictures bearing faces of people.

The researchers found little to no effect of AND and concluded that the possibility of the substance being a pheromone was slim.

Human pheromones studies have also focused on androstadienone, a chemical found in the sweat of men. There is evidence to suggest that this chemical increases sexual attraction and affects mood. It is also said to play a role in social cognition. Other studies revealed that androstadienone can increase a woman’s sexual drive especially when she’s exposed to the chemical just before ovulation.

Do human pheromones exist?

Evidence for the existence of pheromones in humans is weak and inconclusive. However, the possibility of a breakthrough in pheromone research should not be completely ruled out as researchers are still on the hunt for molecules that can function as pheromones in humans.

Originally posted on Health in Vitro