Oxytocin: What Is The Love Hormone & How to Increase It

Oxytocin is famous as the 'love hormone,' and the real science is more surprising. Here's what oxytocin actually does, its dark side, and how to support connection.

Oxytocin is the chemical the internet loves to love. It’s been crowned the “love hormone,” the “cuddle chemical,” even the “moral molecule”: the thing a hug, a kiss, or a knowing glance supposedly floods you with. The real science is more surprising, and more useful. Oxytocin works like a volume knob for social information, and it can turn up warmth and bonding, or bias, envy, and even aggression, depending on context.

Here’s what oxytocin actually does, where the popular story breaks down, and how to support genuine connection (without believing the hype).

What Is Oxytocin?

Oxytocin is a hormone and neuropeptide made in the hypothalamus and released into the bloodstream by the posterior pituitary gland. It has clear, well-established physical jobs, especially in childbirth and breastfeeding, and it’s involved in social behaviors like bonding and attachment (oxytocin overview, Cleveland Clinic).

Oxytocin is associated with social processes including trust, parent-infant bonding, romantic attachment, sexual arousal, and recognition. That phrase, “associated with,” is doing a lot of work in that sentence, and it’s the theme of this whole article. The popular framing has gotten far ahead of the evidence.

What Oxytocin Really Does

So what is it doing? The leading explanation is that oxytocin turns up the brain’s attention to social cues, whatever those cues happen to be (the social salience model).

That changes the picture. Oxytocin seems to amplify what is already in the room: cooperation or competition, safety or threat, in-group warmth or out-group wariness. In a review of the human research, about a fifth of the published studies reported the opposite of warmth: more envy, more mistrust, more wariness of outsiders. The same dose can nudge you toward connection or toward suspicion, depending on the situation and who you are.

It works largely by modulating the amygdala and its links to the brain’s reward circuitry, shaping how much weight you give to social signals and dialing down fear responses to people who seem safe.

The Dark Side of the “Love Hormone”

In the lab, oxytocin can sharpen the line between “us” and “them.”

• In-group favoritism. Across five experiments with a nasal spray, oxytocin increased favoritism toward the participant’s own group and, to a lesser extent, put-downs of outsiders. The paper’s title calls it “ethnocentrism.”
• Envy and gloating. In a rigged game of chance, oxytocin increased envy when people won less than their opponent, and schadenfreude (gloating) when they won more. General mood didn’t budge.
• “Tend and defend.” Researchers describe oxytocin as supporting a tend-and-defend pattern: bonding and trust within your group, paired with wariness or defensive aggression toward outsiders who seem threatening. Later work found it could even improve coordinated attacks on an out-group when that benefited the in-group.

None of this makes oxytocin “bad.” It makes it parochial: it strengthens whatever social bonds and boundaries are already in play.

Oxytocin Myths & Misconceptions

A few other oversimplifications are worth retiring:

Myth #1: Oxytocin Is a “Female” Hormone

Because it was first identified through female reproduction, oxytocin is often stereotyped as female. In reality, all bodies produce and use it, though men’s and women’s systems use it somewhat differently.

Myth #2: Oxytocin Is Purely an “Anti-Stress” Hormone

Oxytocin can reduce stress hormones, but that’s not guaranteed. A person’s social history, including early hardship, can change how they respond to it (research on oxytocin and early life stress).

Myth #3: Oxytocin Is “the Hormone of Motherly Love”

Oxytocin supports nurturing behaviors like feeding and bonding, and it’s one contributor among many. In a study of mice bred without oxytocin, maternal care continued anyway.

Oxytocin’s Forgotten Sibling: Vasopressin

Oxytocin has a closely related molecule, vasopressin, identified around the same time and differing by just two amino acids. The two evolved from the same ancestral peptide and work alongside each other to support social and biological functioning.

Broadly, oxytocin rises with social contact, pair bonding, relaxation, reproduction, and sensory and memory processing, and it’s associated with reduced anxiety. Vasopressin is linked to positive social behavior, partner selection, attachment, attention, and territorial behavior. It also appears to matter for pair bonding and parenting.

What Oxytocin Is Well-Established For

After all those caveats, here’s what’s rock-solid:

• Childbirth: it’s central to the contractions of labor.
• Breastfeeding: it triggers the milk let-down reflex.
• Early parent-infant bonding: your body’s own oxytocin, released during birth, skin-to-skin contact, and breastfeeding, is genuinely linked to bonding behaviors in both parents. Research pooling 33 studies found it goes together with more affectionate parenting in mothers and more playful, stimulating parenting in fathers.

The strongest evidence is for your body’s own oxytocin doing physical jobs, far more than for sniffing it from a bottle to feel more loving.

Can You Really “Boost” Oxytocin for Trust?

Much of the popular oxytocin story comes from studies where adults sniffed an oxytocin nasal spray and supposedly became more trusting. That research is on shaky ground.

The famous origin point was a 2005 Nature study reporting that an oxytocin nasal spray increased trust in an investment game. The headline finding came from 29 people per group, and it barely cleared the bar. Since then:

• When other teams ran the experiment again with far more people, the trust effect didn’t show up.
• A 2015 review added up every trust-game study to date and found no reliable effect at all.
• A critique bluntly titled “Intranasal Oxytocin: Myths and Delusions” found that at most 0.005% of a nasal dose reaches the fluid around the brain. That raises the question of whether it affects the brain at all.

There’s also the “moral molecule” narrative, popularized in a bestselling book and a widely read Harvard Business Review piece. The management advice in it (recognize people, give autonomy, build relationships) is perfectly sound. The claim that it works by reliably raising employees’ oxytocin is best treated as a metaphor (a review of the book’s claims).

So what does that mean for “increase your oxytocin” tips? Measuring oxytocin in blood, saliva, or urine is unreliable, and you can’t crank a “level” on command. Treat the suggestions below as good ways to build connection and wellbeing, which is the point anyway.

6 Ways to Build Connection (Oxytocin Optional)

The behaviors below are linked to oxytocin in the research, and more importantly, they’re simply good for your relationships and mood. Do them for the connection.

Make Reciprocal Eye Contact

Eye contact is a classic way to spark a sense of connection (and is associated with oxytocin release). In The Power of Eye Contact, Michael Ellsberg suggests three easy steps:

1. Glance at someone briefly, then look away.
2. Look again.
3. If they return your gaze, that’s a sign they’re open to engaging.

Uncomfortable with eye contact? Look at the bridge of the nose or the eyebrows. Your conversation partner usually can’t tell the difference. See our guide to unforgettable eye contact for more.

Talk to the Right People

Social isolation is hard on mental health, and real conversation is one of the best antidotes:

• Favor voice and in-person over text. In one study of girls comforted by their mothers after a stressful task, hearing a voice lowered stress hormones and raised oxytocin. Instant messaging did neither.
• Tell stories. Reading one aloud or recounting one from memory is a powerful bonding act. One study found a single storytelling session lowered stress and pain in hospitalized children.
• Don’t over-fear a little gossip. Connecting over shared observations is part of how humans build bonds and norms. Just keep it kind.

Need an opener? Here are 57 conversation starters for any situation.

Form Authentic Relationships

Connection buffers stress and supports empathy and cooperation. There’s no “correct” number of friends, so find the type and quantity that fits you. A few principles:

1. Be honest with yourself about the relationships you actually want.
2. Be your real self, and don’t perform.
3. Get clear on what you want from a relationship.
4. Don’t assume people know how you feel about them.
5. You don’t have to be everyone’s friend.

Struggle to make friends as an adult? Try these five steps.

Use Social Touch

Touch is one of the most reliable triggers for connection. Skin-to-skin contact between parents and newborns is so valuable that some maternity systems build it into standard care. For adults, a hug, a handshake, or a massage can all give you a sense of being cared for.

Cuddle with a Companion

Cuddling is an evolutionary social behavior that regulates body temperature and is associated with that warm, bonded feeling. No human handy? Pets count. Affectionate time with a cat or dog is associated with rises in owners’ oxytocin.

Exercise Regularly

Physical activity is associated with oxytocin release, with more intense or contact-heavy activity (think running to exhaustion, grappling) showing larger associations than a gentle jog. But you don’t need the chemistry as motivation. Exercise is one of the best things you can do for your mood either way.

A note on all of the above: none of this is medical advice, and it’s always best to consult a doctor with any health questions.

Oxytocin FAQs

Why is oxytocin called the “love hormone”?

Because levels tend to rise during intimate, affectionate moments, and early studies linked it to trust and bonding. But the label oversells it. Oxytocin turns up your attention to social cues, and it can heighten envy, bias, and wariness as readily as warmth. “Social spotlight” is a better nickname.

Does sniffing oxytocin make you more trusting or loving?

Probably not reliably. The headline “oxytocin spray increases trust” studies didn’t hold up when researchers ran them again, and very little of a nasal dose even reaches the brain. Be skeptical of products promising bottled connection.

Can oxytocin have negative effects?

Yes. In studies it has increased in-group favoritism, envy, gloating, and defensive aggression toward outsiders. It strengthens the social boundaries and bonds already in play.

What happens when oxytocin is low?

Some research has linked lower oxytocin to depression, anxiety, and reduced empathy. Those things tend to go together, which is a long way from proof that low oxytocin causes them, and the measurements themselves are unreliable. Treat single “low oxytocin” claims cautiously.

What’s the difference between oxytocin and vasopressin?

They’re closely related peptides that work together in social and bonding behavior. Oxytocin leans toward affiliation, relaxation, and reduced anxiety; vasopressin leans toward vigilance, partner selection, and territorial behavior.

Want to Go Deeper?

The talk below helped popularize the oxytocin-and-trust idea. It’s a useful introduction, though the specific “moral molecule” mechanism is contested, as covered above. Watch it with that grain of salt:

Oxytocin Takeaways

• Treat “love hormone” as a marketing label. Oxytocin works more like a volume knob for social attention.
• Watch for the dark side. In-group bias, envy, and even aggression toward outsiders come along with the warmth.
• Give the physical roles their due. Childbirth, breastfeeding, and early parent-infant bonding are where the evidence is clearest.
• Be skeptical of nasal sprays and “boost your oxytocin” hype. The trust studies didn’t hold up, and barely any of a nasal dose reaches the brain.
• Build real connection anyway. Touch, eye contact, conversation, and time with people you love are worth it for their own sake.

If you’d like to put the connection part into practice, start with our guide on how to make friends.

References

• Shamay-Tsoory, S. G., & Abu-Akel, A. (2016). The social salience hypothesis of oxytocin. Biological Psychiatry. PubMed
• Bartz, J. A., et al. (2011). Social effects of oxytocin in humans: context and person matter. Trends in Cognitive Sciences. PDF
• De Dreu, C. K. W., et al. (2011). Oxytocin promotes human ethnocentrism. PNAS. Read the paper
• Shamay-Tsoory, S. G., et al. (2009). Intranasal administration of oxytocin increases envy and schadenfreude (gloating). Biological Psychiatry. PubMed
• Zhang, H., et al. (2019). Oxytocin promotes coordinated out-group attack during intergroup conflict in humans. eLife. Read the paper
• Kosfeld, M., et al. (2005). Oxytocin increases trust in humans. Nature. PDF
• Nave, G., Camerer, C., & McCullough, M. (2015). Does oxytocin increase trust in humans? A critical review of research. Perspectives on Psychological Science. PubMed
• Leng, G., & Ludwig, M. (2016). Intranasal oxytocin: myths and delusions. Biological Psychiatry. PubMed
• Declerck, C. H., et al. (2020). A registered replication study on oxytocin and trust. Nature Human Behaviour. PubMed
• Flanagan-Cato, L. M. (2012). Are you responsible for your hormones? Review of The Moral Molecule. Cerebrum: The Dana Forum on Brain Science. PMC
• Parent-infant oxytocin systematic review (2023). PubMed
• Seltzer, L. J., et al. (2012). Instant messages vs. speech: hormones and why we still need to hear each other. Evolution and Human Behavior. PMC
• Oxytocin overview. Cleveland Clinic. Oxytocin overview