How Falling in Love Physically Changes Our Genes
To the immune system, falling in love is like a viral infection. Here’s how it happens.
Love is a fascinating thing to ponder.
It happens to all of us. It comes on like a rush of adrenaline that knocks us off of our feet. It radically reshapes our lives. It consumes us. Anyone who’s ever experienced it knows exactly what I’m talking about.
Sometimes love drives you literally crazy. Don’t worry, it’s not just you, that happens to all of us. And there are biological reasons for this. Love has the power to make us all a bit mad. Like a drug, it keeps us up through the hours of the night.
Writers from as far back as ancient Rome have been talking about the powerful, captivating experience of falling in love. The ancient Roman poet, Ovid, wrote about this over 2,000 years ago:
Let your leanness show your heart: don’t think it a shame
to slip a cape over your shining hair:
Let youthful limbs be worn away by sleepless nights
and care, and the grief of a great love.
Love is forever and enduring as a concept. Humanity never grows tired of it. But when we fall in love as individuals, it’s a physical process, not just an idea. As humans, we all fall into love, and we all fall out of love. No rush of romantic love is permanent. All good things must transform into something else, or come to an end.
Ovid himself said this 2,000 years ago, also:
A sweet form is fragile, what’s added to its years
lessen it, and time itself eats it away.
Violets and open lilies do not flower forever,
and thorns are left stiffening on the blown rose.
The reason for this is that love isn’t just a feeling, but a biological process, like every other. Everything that’s alive will eventually die. Everything that’s newly born will eventually grow into adulthood. Even the tiny microorganisms that our world couldn’t exist without going through a series of changes called a “life cycle,” whereby they transform themselves and seek different environments in order to procreate.
And that’s what human love is, it’s how we procreate. Sticking together and maybe starting a family is the tricky part.
And from ancient poetry to cutting-edge science, much of our literary history has sought to understand this magical process we all undergo.
Fortunately for us, we live in the era of modern science and science has a lot to say about love and relationships. Some of the information you may find can help you understand what’s happening and why. And scientific experiments help us find out what the average human experiences in their own bodies when they fall in love.
Falling in Love Strengthens the Immune System
Falling in love may actually change us on the genetic level. Researchers are only now beginning to study the effects of the experience of love on the smallest levels of our biology.
A small 2018 study took 47 women, of whom about half were in love, and studied them for over two years. The goal was to see what changes would take place genetically and how those changes would regulate the immune system when a woman is in love.
And the results were astonishing: according to your immune system, falling in love is perceived by the body like a viral infection.
Analyses revealed a selective alteration in immune cell gene regulation characterized by up-regulation of Type I interferon response genes associated with CD1C+/BDCA-1+ dendritic cells (DCs)…These effects emerged above and beyond the effects of changes in illness, perceived social isolation, and sexual contact. These findings are consistent with a selective up-regulation of innate immune responses to viral infections (e.g., Type I interferons and DC) and with DC facilitation of sexual reproduction, and provide insight into the immunoregulatory correlates of one of the keystone experiences in human life.
You read that right; the findings of the immune response were “consistent” with a viral infection. Such findings were unrelated to how often the women got ill or engaged in sexual contact. Being or falling in love in itself changes the genes involved in the immune system.
While we don’t know exactly why there are a few curious facts about this.
One reason, the authors speculate, is “a functional, prophylactic defense against potentially novel viral infections,” where the immune system activates its defense mechanisms to protect against possible infections.
This makes sense since being close to another introduces a new source of microbes, and the immune system is ready to overcome this (for love). One could say that, according to this study, being in love strengthens the immune system.
Nonetheless, the fact that the experience itself seems to be the catalyst that changes the genetic regulation of our immune cells is by and large the most incredible part. For proponents of philosophical free will like myself, people who believe that we have autonomy to greater or lesser degrees, and that physical biology isn’t destiny, this is a landmark finding.
Long Distance Love
The most astounding part is the study findings held steady irrespective of proximity or perceived isolation. It didn’t even depend on sexual contact. It didn’t happen through an exchange of pheromones, like when two organisms spend a lot of time close to one another, and their menstrual cycles shift and align.
The physical response to falling in love held steady from afar. It appears as if two people can fall in love, one in California the other in South Africa, and they will still experience the same genetic responses as two people who’d fallen in love in the same room.
According to the body, falling in love with a thumbnail photo of someone’s face isn’t discernibly different from falling in love with their actual face. Either way, we fall in love with an idea, whether it’s the idea of their face or the idea of a picture of their face.
We’re much like the very atoms that we’re composed of, you and I — us humans. Anyone who remembers high school science class remembers that electrons repel one another quite fiercely, keeping a comfortable distance between themselves and other electrons.
But certain outside forces can cause electrons to mutually attract—as if the two electrons had been put under some spell and suddenly fell in love. Such is the way with human endeavors.
From a scientific perspective, we understand some fundamental ingredients of love, the basic building blocks of how it happens, but we don’t understand everything — nor can we predict instances of love with any sort of accuracy.
The most detailed computer algorithms of today, ones that can map the Genome and display the light coming into our atmosphere from the entire visible universe seemingly effortlessly, cannot predict the seemingly random nature of this very human phenomenon.
This small study is far from complete, though it’s refreshingly new, and there’s still much to learn about the immune system’s response to the experience of falling in love versus viral infection, not to mention other emotional states one could experience throughout their life.
Who knows what potential medicinal treatments could be discovered, and philosophical implications uncovered with more data to analyze.
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