Chemistry of love

Chemistry of love I am a mixture of a rational engineer and a warm hearted poet, I like philosophy and psychology and this combination makes me wonder how all these so irrational things like falling in love work in our mind and body. Although falling in love and long lasting love are not very rational, we do try to explain these complex feelings in a scientifically way. Although mankind is quite a highly evolved being, almost all of our emotions are still chemical processes in our body. Every day, many hormones and other chemical substances travel through our body to regulate almost all important processes within our body, but they also control our mood and feelings. It doesn't sound very romantic but when it comes down to it, scientific seen falling in love and long lasting love are nothing more than some chemical processes in our body. The often pleasant feelings must inspire us to perform reproduction with the sole intention of passing on our genes because in the end we are just the transportation of our gene set. This may not sound very romantic but romance is also activated by these chemical processes. This page is about the chemistry of love, it's fun to philosophize about this, regards, Hein Pragt

Copyright © Hein Pragt.

What is the chemistry of love

I am not a scientist and not a doctor but I like to read a lot about these subjects and attend lectures about this topic. I learn a lot and I like to philosophize and write about these topics. Don't take what I write as absolute science, but if you are inspired just google the scientific articles that I based my writings on. I can assure you it's fun and educational.

Strictly speaking, falling in love is simply a caused by a chemical reaction in our body the moment we perceive a compatible person with all of our senses. In recent years there have been indications that humans also use pheromones, many animals use these substances to unconsciously indicate to each other that they are prepared to mate. So for fun we could also speak of love at first smell instead of love at first sight. But suddenly you are in love and suffer from weak knees and butterflies in your stomach. People sometimes speak of chemistry between you and the other, but you can take that very literally. It's the chemicals in your body that give you a pleasant feeling and take care of all the side effects of falling in love, including the butterflies in your stomach.

I recently attended a lecture on this subject and it was made clear that most humans naturally have a kind of defense against someone who gets too near. Most people find this uncomfortable and most people also recoil when someone gets too near. The size of this zone can differ per person, but almost everyone has such a zone. In order to mate and care for offspring, this natural defense has to be broken otherwise lovers could not come close together to mate. This is exactly what the falling in love hormones do, they make you feel good and they adjust parts of the brain. Critical rational and defensive parts of the brain are put out of order, when one is in love one can no longer think rationally. All this is meant to encourage people to come closer and mate as a pure evolutionary behavior. But it really feels so good, that is the reward of our brain for trying to reproduce ourself.

Because of the long time that human children are depending on their parents, it's difficult for humans to raise a young child on their own. That is why the chemicals remain present for a while after mating so that both partners grow closer together. But even after a longer period of time, the mating still has consequences for the partner bonding. During intercourse chemicals are released that also affect certain parts of our brain. In humans, this ensures that even after birth the partners remain together which is to the benefit of the offspring. It doesn't sound very romantic but love and partner bonding are chemical processes in the human body and physical intimacy is a natural method to reactivate these chemicals.

The most well-known substance is phenylethylamine (PEA), which occurs naturally in your body. It resembles amphetamine and also has about the same effect. Exciting attractions such as a roller coaster and also eating chocolate can give you an extra dose of PEA. A lot of people eat chocolate when they are a little down to induce a pleasant feeling. That is why chocolate also works as a medicine against heartbreak. PEA ensures that the neurotransmitter dopamine is released, which is the substance that does all the work. Dopamine in turn provides the production of the substance oxytocin (a cuddling stimulator). Another substance is norepinephrine, which also results in a euphoric feeling. It takes care for the production of adrenaline, making it seem like you have endless energy. This enormous disturbance of the balance in the body causes people in love to no longer really think rational and the emotion center (temporarily) takes over from the normal conscious cerebrum. .

As with other drugs, habituation also occurs with falling in love, the dose of PEA to stay happy must be higher to give the same effect but it decreases slowly. After usually about one year, everything is stable again and another group of substances takes over, the endorphins that are more like the soothing painkiller morphine. These ensure that you have a relaxed feeling when you are with your partner. Of course there's a lot more to love than just messing around with chemicals, the process that causes this are not well analyzed yet. Why we fall in love with just that one person from a large group is also not well explained.

Pheromones and falling in love

In recent years there has been increasing evidence that humans also secrete and can perceive pheromones. Most animals use these substances to unconsciously pass messages to each other that they are ready and willing to mate. Pheromones are probably captured by an organ in our nose. If humans also turn out to have pheromones, they probably won't be as powerful as those of animals. some chemical substances similar to the male and female love hormones trigger a clear brain activity in the partner. Researchers of the Karolinska Institute in Stockholm discovered that during a brain scan of two dozen volunteers, part of the brain that, regulates physical intimate behavior, "lighted up" in women when exposed to a substance similar to testosterone. With men, the same hypothalamus reacted when confronted with estrogen. Importantly, the substances produced no effect due to odor, the researchers see this as a very strong indication that so-called pheromones do indeed occur in humans.

Hormones and love


Estrogen is usually referred to as a female hormone because it plays an important role in the development of female body characteristics. Also it is responsible for regulating the menstrual cycle and pregnancy. It also occurs in much smaller amounts in the male body. The hormone is produced by the ovaries of a women. It then plays an important role in the physical development in the puberty, such as the growth of the uterus and vagina and enlargement of the breasts and genitals. In men it is unclear what function estrogens have. Too much estrogen can decrease the desire for men for physical intimacy. A British study has found that women with a lot of estrogen are generally considered more beautiful by both men as women. Scientists at the University of St Andrews photographed the faces of 59 women between the ages of 18 and 25. They also analyzed the women's estrogen levels. Then they asked fifteen men and fifteen women to indicate which women they found most attractive. This showed that the women with a lot of estrogen scored the highest. According to the scientists, the explanation for the phenomenon is very logical: men fall for fertile women. They recognize them by the large eyes and lips and the smaller nose and jaws. These are also the characteristics that mainly occur in women with a lot of estrogen, the hormone that is very important for fertility.


Testosterone is a real male hormone, it is a compound of testis (Latin for testicle) and steroids. Many animal species produce testosterone, but in females the amount of testosterone is significantly lower than in males. During the development of the embryo, it provides the development of the male primary body characteristics and during puberty it causes the development of the male secondary sexual characteristics such as deep voice, pubic hair and muscles. After puberty, testosterone maintains the masculine reproductive system, the male libido. In women it is also responsible for the libido and this is also a good explanation of why men are generally more interested in physicality than women.

Last update: 20-08-2021

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