How do you know if you love someone? It's difficult to say. Even when you've been seeing someone for a while and are in a committed relationship, there's always that lingering question about what true love is, and whether you and your significant other are in it or not. Of course, there's no one-size-fits-all checklist for the signs you're in love, especially since falling in love requires a range of incalculable factors, from feelings of ease to sexual attraction—but there are a few hints to look for along the way. Below, we've collected a few science-backed signs of true, unwavering romantic love.
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Instead of relying on input from friends and family members to work through your feelings, pay attention to the signs that say you're seriously smitten.
1. Your eyes are drawn to their face.
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If you're wondering whether it's lust or love, take note of where your eyes go first when you look at your partner. It sounds cliché, but gazing into someone's eyes really is a science-backed sign you're in love.
In a 2014 study published in the journal Psychological Science, researchers asked volunteers to look at photos of strangers and decide whether they'd be interested in that person in a romantic versus sexual way. And it turns out, their eyes were a dead giveaway for which they'd choose.
When the volunteers had a sexual desire for the person in the photo, they spent more time looking at the image and their eyes were drawn to the person's body. But when it felt like romantic love, their gaze was drawn to the other person's face.
2. You've started breathing in sync with them.
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Humans naturally start to mimic another person's body language and breathing when they're feeling connected, and that holds true for couples who are in love.
A 2017 Scientific Reports study of 22 long-term couples found that when the two were spending time and sitting together—even when they weren't touching—their breath and heart rates naturally fell into time with each other. If one was in pain and they weren't able to touch, the connection was lost, but bringing contact back helped them sync up again.
Next time you're cuddling, see if your chests are rising and falling together. If they are, it could be love.
3. The world seems like a better place.
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Everything's rosy when you're in love—and science proves it.
A 2014 study of 245 young adult couples published in the Journal of Personality found that being in a relationship helped individuals generally feel less neurotic and more optimistic. If you've noticed your own attitude changing, you might be gearing up for a healthy, long-term relationship.
4. You laugh at all of the same things.
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Research published in Evolutionary Psychology found that laughing at another person's jokes was a sign of dating interest in that person (especially if it's a woman laughing at a man's joke).
But the best signal of romantic attraction was if both people were cracking up together. Laughter shows warmth, so giggling together means you're feeling a mutual connection.
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5. You don't feel like you have to keep secrets.
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Intimacy is the biggest factor that sets love apart from the physical attraction you feel in the early days of dating, says relationship therapist Marisa T. Cohen, PhD, co-founder of the relationship lab Self-Awareness and Bonding Lab and associate professor of psychology at St. Francis College in New York.
"Intimacy involves self-disclosure," she says. "It means allowing your innermost feelings and desires and needs to be known." When you let yourself open up to your partner, it shows that you very well might be in love.
6. You've been obsessing over your partner.
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When you're in love, it's hard to focus on anything else—and that could be your body's fault.
According to research from Loyola University, people who are in love have lower levels of serotonin, which also happens to be a common occurrence in people with obsessive-compulsive disorder.
"This may explain why we concentrate on little other than our partner during the early stages of a relationship," said obstetrician-gynecologist Mary Lynn, DO, in a news release.
7. You include your partner in your stories and plans.
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"There's a big shift when 'I' becomes 'we,'" says Cohen. "You go from focusing on your wants, your needs, your desires to the needs of the couple."
That's not to say that you'll suddenly lose your individuality, she says, but it could mean some subtle changes. When you're in love, you might immediately ask if your S.O. can tag along to a party, or make a note to bring your partner to the great sushi place you just discovered.
8. You've stopped trying to impress anyone else.
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Evidence from fMRIs shows that when people who are in love see a photo of their lover, the parts of the brain associated with reward and motivation light up, according to research published in The Journal of Comparative Neurology.
Now, that's totally separate from the part of the brain responsible for sexual interest and sexual activity. The findings led researchers to the conclusion that when someone is in love, their brain is programmed to focus solely on that person and to put other potential lovers on hold. If you've stopped thinking about who else might be out there, you could be tapping into a primal instinct of mating for life.
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9. Your physical pain levels have dropped.
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Sure, love can be an emotional rollercoaster, but it does also function as a natural painkiller. Researchers from a 2010 study used MRI to study the brains of college students who'd entered a relationship within the past nine months. Then, they applied mild pain to the students' hands.
The participants' senses of pain decreased way more when looking at a picture of their S.O. than when looking at a picture of an equally attractive acquaintance.
10. You feel more open to trying new things.
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Sometimes, change is good. And studies show that when you're just starting to fall in love, your sense of self changes.
"When we're with a partner, we crave these new experiences, and we can learn more about ourselves," says Cohen.
You start exploring new parts of your personality, especially if your partner mentions she admires those traits, and you're more open to trying new things. That willingness to change for another person is one of the first signs that you're feeling a little something more than platonic love.
11. Your stress levels have been through the roof.
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Whoever said love should be easy probably doesn't have much of a relationship history.
When researchers compared hormone levels of couples who'd fallen in love within the past six months to people who were single or in long-term relationships, the recent lovebirds had higher levels of the "stress hormone" cortisol.
The results, which were published in the journal Psychoneuroendocrinology, demonstrate that when you're in a budding relationship, the initiation of social contact can cause an arousing, stressful reaction in the body—which makes sense when you think about the butterflies you get from a date-night invite or a "good morning" text.
12. You're not afraid of investing time in them.
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Psychologists in a 2011 study out of Purdue University found an "investment model" in romantic relationships. In short, they found that people were more likely to commit if they were more satisfied, if the alternatives were less appealing, and if the investment they put in was sizable enough.
Do you feel like you can't imagine anyone better than your partner, and like you've already been putting plenty of energy into it? If so, it might be one of the major signs you're in love.
13. You consider him or her to have similar values.
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Forget the whole opposites-attract thing.
"What sets the basis for a long, loving relationship is you want to be with someone who's similar to you," says Cohen.
But don't break up just because your partner is into baseball and you prefer football; those surface-level things aren't important, says Cohen. What does matter are your values and morals, which will set the foundation for a strong relationship.
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14. You put them above yourself.
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Research published in the European Journal of Psychology shows that people who are in love romantically have higher levels of "compassionate love" than people who identified as not in love.
Compassionate love involves putting other people before yourself. Do you agree to go to boring movies your partner is excited about? Jump up to grab him a glass of water so he can stay relaxed? Putting him first signals that you care deeply about him—and just might be one of the signs you're falling in love.
15. You wonder what their five-year plan is.
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When you're really getting close to someone—whether that's a friend or a partner—you'll probably want to know what their goals in life are, Cohen points out.
If you're starting to fall in love, you might find yourself asking "things that require you to focus on the future and really dig deep and have a sense of self-awareness about what you want out of life," she says.
By wondering about marriage and kids, you're showing that you care enough to learn about his long-term goals.
16. They put you at ease.
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Studies show that romantic partners boost levels of the "love hormone" oxytocin (thus the nickname). Oxytocin, in turn, increases feelings of safety and calmness. When the initial butterflies make way for feelings of contentment, it could be a sign you've gone from infatuation to honest-to-goodness love.
Wrapping Up
That's it for our spin on how to tell if you love someone, but be sure to check back in with us soon for more tips when it comes to life and love. You can also sign up for our newsletter to enjoy hit pieces on health, entertainment, and travel.
