1. Home
  2. /
  3. Love
  4. /
  5. Do Pupils Dilate When You Like Someone? What Science Says

Do Pupils Dilate When You Like Someone? What Science Says

Sophie Simons
July 26, 2023

You must have seen it in movies; when someone’s about to kiss or confess their love, their pupils grow larger, showing their increased level of excitement and happiness. That’s not just in stories; it happens for real, too.

When there’s a spark between two people, their pupils can dilate like they’re catching that electric vibe. But it’s not just love and connection that play a role in pupil size; there are other factors, too. Threat, fear, or just being super-focused on something can also make your pupil change size.

Emotions are partially responsible for pupil dilation and constriction, an involuntary response that the eye’s autonomic nervous system controls. 

You gotta be careful – your eyes can give away a lot of your secrets!

When you see someone’s eye dilating, you can assume that a silent conversation is going on. Naturally, people are attracted to larger pupils as they seem to romanticize the whole scene. According to research, “The pupil correlates with attraction and arousal between love interests.” 

Let’s dive into the article to find out if the idea of your pupils dilating is just imagination or if there’s some science behind this occurrence.

What Is a Pupil?

The black opening in the middle of your eye (positioned in the middle of the iris) that controls how much light enters the eye is known as Pupil. Iris is the colored ring around the pupil, and it has muscle fibers that control the size of the human pupil.  

In bright light, the iris makes the pupil smaller, and in low light, it goes bigger. This size change is called pupil dilation and contraction, and it happens automatically.

Normally, pupils hang out between 2.0 and 4.0 mm, but they can double in size in the dark. When you are feeling love or attraction, your pupils get bigger.

Throughout history, folks thought bigger pupils were attractive. Back in the Middle Ages, certain attempts were made to enlarge the size of the pupil. Nowadays, people use contact lenses to get the desired big eye look.

The Science Behind Dilated Eyes

When you have an intimate interaction with another person, healthy hormones like oxytocin, dopamine, and serotonin are released. This can happen with a hug, a pleasurable conversation, or just feeling a deep connection. 

Usually, with this release, the iris muscles will relax, leaving the pupils to dilate. It’s a response that comes with strong emotions, whether love, fear or even anxiety. It can result from looking at the person in real-time, seeing a photo, or speaking to them via a video call. 

As the person experiencing the reaction, you’re usually unaware of the response. You do recognize that you have a strong desire to see that individual more, and often, when someone looks at you with dilated pupils, it’s obvious there’s a strong connection. 

One thing to remember when you see another person with large pupils is that this isn’t always an indication of love and attraction. There can be many reasons for people to have enlarged pupils that have nothing to do with you – don’t jump to conclusions.

Does It Mean Attraction?

Pupils Dilate When You Like Someone

A Study conducted in 2012 experimented on 325 males and females with different romantic and sexual orientations. They played erotic videos and monitored the pupil size of all the people during this experiment. The results of this study revealed that the pupil size of heterosexual women and bisexual men became larger while they were watching the videos. 

Another study, Evolution and Human Behavior revealed that it is possible to examine someone’s attraction and sexual interests by checking the size and darkness of their pupils. 

The hormones of a human also play a vital role in the dilation of the pupil. For example, in another study that experimented on women (Half of them were taking birth control pills while others were not). The researchers showed them intimate pictures on the computer screen and observed an increase in the pupil size of the women who were not taking any birth control. At the same time, the women who were taking birth control didn’t show any changes in their pupil dilation.

The study shows that there is a direct link between emotions and pupil dilation. Moreover, intelligent people are more likely to have dilated pupils than average people because they pay attention to things around them. However, pupil dilation shouldn’t always deceive your decision-making process. 

Other Factors that Dilate Your Eyes

There can be various other reasons for enlarged pupils. If someone is looking at you with large pupils, it doesn’t always mean they are in love with you, but they can be drunk, caffeinated, or have an involuntary bodily response. 

1. Threat or Fear

One major reason for pupil dilation can be threat or fear. Fear and love are just sides of the coin, and these are very close. Just like oxytocin is released when there’s a happy situation, it also gets released when there is a perceived threat or someone is in a fearful condition. 

2. Alcohol & Caffeine

When someone drinks coffee or takes any caffeinated product, they experience a fight or flight response, which increases the size of their pupil. When someone consumes alcohol, they experience a less flow of blood in the brain, and the adrenaline flight and fight response cause the pupil to dilate. 

3. Optometry Induced

Optometry Induc is a process in which eyes are dilated on purpose to examine the retina in detail. The doctors put some drops in the eyes that last several hours after the treatment process. Patients who go through this process are often asked to wear sunglasses because any flying object or dirt can affect their eyes. 

4. Increased Attention

Some researchers also believe that pupil dilation may be because when someone is paying a lot of attention. But this goes back to the point of attraction because one pays attention only when they are attracted to someone or something. However, not all types of attraction mean love, romance, or any sexual intentions. While paying attention, the pupils dilate to allow more light to enter and help us focus more on the subject

Cause for concern 

The size and shape of your pupils should be relatively consistent, enlarging and reducing to normal size with regularity. If you notice a considerable change in this part of your eye or in each eye, it’s wise to reach out to a trusted ophthalmologist to diagnose a potential underlying cause for the change. 

A difference in size can be associated with various circumstances, but more serious reasons can exist, including the possibility of a brain incident or other rare conditions like Horner’s syndrome

You could also have had an injury previously to the eye that can have this effect. In any event, the variations in size are typically a normal reaction to various stimuli and are often quite harmless. 

You’ll notice a problem if the pupil doesn’t go back to its natural size and if the change is significant.


Pupils can dilate based on intense emotions like falling in love with someone, being attracted to another person, or even having a sense of fear or panic, like if you believe a new relationship won’t stand the test of time. 

While this physical reaction gives you away to the other person, you’ll be oblivious to the response, not knowing that you’re giving yourself away with a mere look.

Share this:
Sophie Simons

Sophie Simons

Sophie Simons is a leading psychologist with a passion for enriching relationships. Through empathetic counseling and insightful guidance, she empowers couples and individuals to foster deeper connections, resolve conflicts, and create lasting harmony. Sophie's expertise in relationship advice has touched countless lives, making her a trusted source for building fulfilling partnerships.

Love Starts Here

Connect with a therapist for convenient, ongoing support and progress step-by-step. 

Get Started
Love Advice
Dating, Relationship and Marriage Advice That Works

Join Our Newsletter

Please enable JavaScript in your browser to complete this form.
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram