What Are Pheromones?

Pheromones are substances secreted from one animal to another and are thought to be one way that animals communicate with one another. For example, among animals, pheromones communicate alarm, terrestrial claims, and are involved in sexual and mating signals.

Although the role that pheromones play among animals is well established, it’s less clear what their role is in humans, or whether humans even have pheromones at all. The theory is that if humans had pheromones, they would be located primarily in our sweat glands. It’s hypothesized that pheromones are mostly involved in sexual attraction in humans. But again, research about pheromones in humans is not robust at this time, and more studies are needed to fully understand their role in our lives.

How Do Pheromones Work?

Pheromones are chemical substances secreted to the outside of the body by an animal and then received by another animal. They are thought to be used in communication and attraction. In animals, pheromones are processed by the vomeronasal organ, which is located in the anterior nasal cavity. The vomeronasal organ has receptor cells that detect pheromone signals.

One of the reasons that researchers doubt the existence of pheromones in humans is that we lack functional vomeronasal organs. The theory is that if humans did process pheromones, they would be picked by our olfactory (smell) system instead of our vomeronasal organs.

As for where pheromones are secreted in humans, it’s hypothesized that pheromones could be present in semen, breast milk, saliva, urine, or vaginal secretions. Still, the most prominent theory is that pheromones are secreted in humans by their sweat glands and picked up in similar ways to how human odors are sensed.

Types of Pheromones

There are four main types of pheromones that have been identified in the animal kingdom:

• Releasers, which cause a prompt, precise response
• Signalers, which release information about the animal
• Modulators, which impact emotions and moods
• Primers, which impact endocrine or neuroendocrine responses connected to development and reproduction

Again, no pheromones have been definitively identified in humans, but there are two types of sex pheromones that are theorized to be present in humans. These are:

• Androstadienone, which are connected to males
• Estratetraenol, which are linked to females
  

Functions of Pheromones

It’s clear that pheromones play important roles in the animal kingdom, including among mammals. Some of the roles that pheromones play in animals include:

• Sexual attraction
• Choosing a mate
• Following another animal’s trail
• Communications between parents and their children

In terms of the roles that pheromones play in humans, there is less clear evidence. The main theory is that pheromones play a similar role to the one that odors play in humans. For example, odors from one human to another clue us into some important information, such as:

• Odors may help us identify people who have infections (i.e., noticing that someone doesn’t "smell right")
• Odors can influence who we are sexually attracted to and who we choose as mates
• Odors, along with other cues, can tell us when someone is experiencing stress or fear
• Odors may be able to tell us that a woman is menstruating

Perhaps the most well known theories about pheromones in humans have to do with sex and sexuality. Many people associate scents and odors with sexual arousal, and find certain scents are attractive and certain ones are a turn-off.

The theory is that pheromones might play a role in attracting us to certain people over others. In other words, pheromones—like body odor, physical appearance, and other stimuli—may guide our attraction to potential sexual partners on a more primitive, biological level.

Do Pheromone Products Work?

From spray, perfumes, and colognes, there are numerous products on the market that claim to contain pheromones or are enhanced with pheromones. The idea is that wearing one of these scents will help you attract someone sexually or will boost your sexual compatibility with someone you’re attracted to.

However, it’s not even clear if pheromones exist in humans. There is no evidence that adding pheromones to perfumes and colognes will have a positive effect on sexual attraction, or whether it will have any effect at all.

One study found that many perfumes that are marketed to contain pheromones may not actually contain this substance. The researchers examined 12 perfumes that were marketed under the pretense that they contained pheromones. They found only seven out of the 12 contained synthetic pheromones. The study researchers cautioned buyers to beware of false marketing schemes, noting that, “perfume manufacturers do not seem to follow any scientific protocol in the design and fabrication of these products.”

Although there is no proof that human products containing pheromones play a role in sexual attraction, there is some evidence that pheromone products manufactured for animals may be effective.

For example, one study looked at whether dog collars containing pheromones could reduce fears and anxiety associated with the sounds and experiences of thunderstorms.

The study’s result was positive. As compared to dogs who wore no collars, dogs who wore dog-appeasing pheromone (DAP) collars had significantly decreased fear and anxiety during times that they were exposed to simulated thunderstorms.

A Quick Review

Pheromones are substances that help animals communicate and are thought to be involved in mating, territorial claims, and interactions between parents and offspring. Their role in humans is less clear, with no definitive research proving that humans even secrete pheromones at all. The theory is that if humans did secrete pheromones, they would be released by sweat glands and would be primarily connected to sexuality and emotions.

There is no evidence that perfumes and colognes containing synthetic pheromones impact sexually or play a role in attracting a mate. Research is ongoing to understand the role that pheromones play in our lives, but for now, it's important to be wary of marketing claims about pheromone-containing products.