Love is an essential part of life. Love can be defined as the chemical state of mind that involves the same chemical processes in the brain that occurs during drug addiction.
It can feel effortless in the early stages. But there is a combination of chemical hormones and complex psychological interactions that help in the development of a long lasting love. A 2009 study 1 defined this emotion as “an emergent property of an ancient cocktail of neuropeptides and neurotransmitters.”
3 Stages Of Falling In Love

According to Researcher Helen Fisher, love can be divided into three stages. Each category is governed by a set of hormones. They are as follows:
1. Lust
The initial stage of love is lust. This is an integral part of love. Lust can be defined as a state of intense sexual gratification towards another person.This feeling is developed due to our natural human instinct to mate and procreate with a partner. Some of the signs of lust are:
- You are focused on their body and looks
- You are interested in sex but not in conversations
- You are not interested to discuss real feelings
- You don’t want to spend quality time with them
2. Passion/Attraction
In this stage, we begin to think irrationally and idealize our lover. Attraction is associated with feelings of excitement, wanting emotional connection and intrusive thinking. A 2000 study 2 found that physical appearance is important to humans and certain features appear attractive across individuals and cultures. The brain chemicals that govern passion are norepinephrine, dopamine, and phenylethylamine. The initial stages of feeling good when meeting someone is attraction and not love. Love is a feeling that fades. However, attraction may fade over time. For instance, you can be attracted to someone for their beauty, talents or personality but love is beyond this. Attraction is mainly governed by the hippocampus, hypothalamus, and anterior cingulate cortex of the brain. When activated, these regions can significantly reduce defensive behavior and anxiety and increase trust towards the romantic partner.
3. Attachment and commitment
In this stage, the passion for each other turns into attachment towards your significant other. The hormones responsible for this stage are oxytocin, endorphins, and antidiuretic hormones. A 2001 study 3 found that sexual activity is an important component of the reinforcement of the reward system and this influences the reinforcement of attachment. This also leads to increased levels of dopamine in the brain. Oxytocin promotes bonding and trust that helps in the development of long term love and relationships. The intensity of love often fades but attachment continues to persist and helps you to feel more secure and safe.
Read More About Attachment Styles Here
The Neurobiology Of Love
In the initial phase of love, it begins when an individual regards their significant other as special and unique. This feeling is then followed by focused attention, aggrandizement of traits, and overlooking or minimizing his or her faults. A 2004 study 4 found that it activates the reward system of the brain that results in a reduction in emotional judgment, fear, depression, and also enhances mood. A 2006 study 5 found that emotional dependence, empathy, sacrifice, and obsessive thinking are common in this phase. Sexual desire is also present. However, the desire for emotional union may supersede the intense craving for sex. The two hormones that play a major role in our sex drive are estrogen and testosterone. Our lust and desire to have sex are governed by these two hormones. It is also found that rejection in love triggers protest and rage, which is then followed by despair.
An fMRI study 6 demonstrates that involvement of areas associated with motivation and goal-oriented behavior in love suggests that it is a primary motivation system that triggers the human mating drive. In evolutionary terms, the primary goal of love is the continuation of our species.
Chemicals In The Brain

The sleepless nights, the desire to be with the other person, racing heart are all initial signs of falling in love. These are caused by certain neurochemicals in the brain. Some of them are as follows:
1. Norepinephrine
A 2007 study 7 suggested that the production of adrenaline is governed by the hormone and neurotransmitter, norepinephrine. The adrenaline rush we experience while in love causes the racing heart, sweaty palms or flushed cheeks. A 2018 study 8 found that high levels of norepinephrine can lead to increased joy or loss of appetite. This hormone triggers euphoria and feelings of bliss, increased energy, lack of sleep or appetite, and focused attention on your new relationship.
2. Dopamine
Dopamine, the happy hormone, is released in our brains when we feel good. Some of the activities that stimulate the production of dopamine can include eating, exercising, reading your favorite books. Dopamine has a significant effect on our brain processes that govern our emotional responses and our ability to express pleasure. Our ability to be sociable is also closely tied with dopamine neurons. A 2013 study 9 has shown that people with social anxiety have low dopamine levels. Without dopamine, the physical effects of norepinephrine cannot occur. Dopamine activates the receptors of the brain associated with the pleasure system. Due to this, the euphoria and feelings of enjoyment are increased.
Read More About Dopamine Here
3. Phenylethylamine
Phenylethylamine is responsible for the butterflies in the stomach we feel when we are around our lovers. A 2014 study 10 pointed out that our first attraction towards someone causes our brain to release high levels of Phenylethylamine. This hormone is also responsible for the production of dopamine and endorphins. These are also responsible for making us feel euphoric and energized.
4. Oxytocin
Oxytocin, also known as the love hormone, is a neurotransmitter associated with empathy, trust, sex, and relationship building. Increased levels of oxytocin are released during cuddling and orgasm. A 2008 study 11 found that it can benefit treatment for a number of conditions such as depression, anxiety, or intestinal problems. This neurotransmitter is produced in the hypothalamus. A 1997 study 12 found that an increase in oxytocin associated with birth and lactation might make it easier for a woman to be less anxious around her newborn and to experience and express loving feelings for her child.
5. Vasopressin
After the initial stages of passion and lust are completed, we may begin to experience symptoms of falling out of love. This occurs due to an antidiuretic hormone called vasopressin. This hormone creates the desire to bond and nurture your partner. A 2015 study 13 also found to have strong effects on men because of how it interacts with the male sex hormones, testosterone.
The Complex Chemistry Of Love
Some may believe that love is a complex combination of hormones and chemicals while others consider love as a divine intervention. The euphoria of love may fade with time. But it is important to realise that it’s all in our heads. Love is a complex combination of choices and hormones. One cannot occur without the other.
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