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The Biology of Falling in Love

"We are most alive when we are in love." — John Updike


There may be no better feeling in life than that of being “IN LOVE”. A new love, or even the potential for one, can bring intense feelings of infatuation, happiness, excitement, nervousness, attraction, and lust. Being in love can make you feel energized and euphoric – truly ALIVE! Arguably, there is nothing else like it!

Being in love not only comes with powerful feelings, but you might also experience physical symptoms, such as sweating, dizziness, pounding heart, appetite changes, insomnia and more. What makes us feel this way? Let’s discuss …


The Biology of Falling in Love

Research has shown that “falling in love” is a matter of chemistry – brain chemistry, that is. In one such study, led by Dr. Helen Fisher, researchers propose that there are three main components to falling in love, each with its own set of brain chemicals and hormones. These stages are lust, attraction, and attachment.



Lust derives from our need for sexual gratification. However, it is deeply rooted from our most basic and primal evolutionary instinct to reproduce and propagate the species.

The brain’s hypothalamus is key in creating the desire to fulfill this evolutionary role. The hypothalamus stimulates the body’s sexual organs (testes or ovaries) to produce sex hormones, estrogen and testosterone. While people often assign these hormones to one gender or the other, both hormones are inherent to both males and females, and both hormones influence libido. Testosterone is known to increase sexual drive in both males and females. However, some females find their sexual drive peaks during ovulation when estrogen is at its highest.



The first spark of attraction stimulates the brain’s reward pathway. Recognizing a potential for reward, the hypothalamus again springs into action producing dopamine. Dopamine is a neurotransmitter and neurohormone. As a neurotransmitter, dopamine relays messages between nerve cells in your brain and the rest of your brain and body - while outside of the brain, dopamine acts as a hormone. Dopamine is released when we do things that bring us pleasure, which is why it is nicknamed the “feel-good” hormone or neurotransmitter.

Dopamine plays an important role in many body functions, including:

• Behaviors involving motivation, punishment, and reward.
• Cognitive functions involving attention, learning, and short-term memory
• Voluntary movement
• Pain processing
• Sleep and dreaming
• Mood regulation

When experiencing attraction, high levels of dopamine and a related hormone, norepinephrine, are released, causing individuals to feel giddy, energetic, and euphoric. Some would equate this feeling to a drug-induced “high”.

Attraction may cause a loss of appetite and trouble sleeping because, in essence, your body wants you to spend more time having pleasurable thoughts of your new love interest, so that you will produce more dopamine. You are becoming “addicted to love”. No, seriously, you are!

And, what’s more, attraction also appears to reduce levels of serotonin, a hormone known to influence appetite and mood.



Lust and attraction can come and go, but it is attachment that seals the deal. Attachment is the predominant factor in long-term relationships. Interestingly, unlike lust and attraction, attachment is not exclusive to romantic relationships. Attachment also appears in friendships, parent-infant bonding, and other close relationships.

During the attachment stage, the hypothalamus is once again leading the charge with the production of two other important bonding hormones – oxytocin and vasopressin. Oxytocin is often nicknamed “the cuddle hormone” for this reason. Both bonding hormones work in the background to remind us why we like our special person(s) and increase our affection for them, so that we will keep them around.


So, there you have it, the biology of love. The brain’s special blend of chemicals and hormones. Not very romantic, is it?
Not to take away from science, but if that is the case, why have there been poems and songs written about love throughout the ages? Why is it so powerful? Can it truly just be biology?

Although, the science is sound, who’s to say there isn’t that one special person(s) out there that makes falling in love, a once in a lifetime experience; physically, spiritually, and emotionally?

This Valentine’s Day we wish you a love you can write a song about.

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