In April 2024, a video went viral on TikTok, claiming that if you’re extra sleepy when you’re around your partner, it means you’re “chemically bonded.” The video’s captions read, “just found out that if ur extra sleepy when you’re around your partner it means you’re chemically bonded. Your body releases hormones like serotonin or dopamine when you’re together, which makes you more sleepy? that’s the sweetest shi i’ve ever heard.”
(via TikTok user @viraj.bagga)
As of this writing, the video had accumulated more than 3.5 million views, 421,000 likes and 104,000 shares. The same claim was spread via numerous viral TikTok videos and X posts.
In short, based on our research we found that while the presence of serotonin and dopamine in the brain can influence one’s sleep-wake cycle, many other factors may also play a role when one “feels sleepy.” In fact, no scientific studies conclude that feeling sleepy around one’s partner is caused by the release of serotonin and dopamine, or that the release of those hormones is caused by that proximity, or that feeling sleepy is a sign of a “chemical bond” between two people.
Based on these factors, we have rated the claim as a “Mixture” of true and unconfirmed information:
- True – Certain brain hormones, including serotonin and dopamine, are known to influence people’s sleep-wake cycles.
- Unconfirmed information – No scientific studies prove that being sleepy around one’s partner is a sign of a chemical bond or is caused by the release of hormones such as serotonin and dopamine.
Serotonin and Dopamine
Dopamine and serotonin are neurotransmitters, chemicals in the brain that transmit signals between nerve cells (neurons). Both hormones play a unique role in regulating various physiological processes, such as the sleep-wake cycle.
“Serotonin is one of the natural body chemicals that controls your mood. It works with melatonin to help control when you sleep and wake up, as well as how you feel pain, wellbeing and sexual desire,” the national health advice service in Australia explains. Serotonin influences sleep in that it’s necessary for the synthesis of melatonin, another important hormone in the brain. Adequate serotonin levels are required for the proper production of melatonin, which then regulates the sleep-wake cycle and timing of sleep onset.
Dopamine, on the other hand, produced by the hypothalamus, is “released when we do things that feel good to us,” such as being in a relationship.
In this case, these things include spending time with loved ones and having sex. High levels of dopamine and a related hormone, norepinephrine, are released during attraction. These chemicals make us giddy, energetic, and euphoric, even leading to decreased appetite and insomnia – which means you actually can be so “in love” that you can’t eat and can’t sleep.
As of now, we have not found any scientific studies proving that being sleepy around one’s partner is a sign of a “chemical bond” or caused by the release of hormones such as serotonin and dopamine. We have reached out to biochemistry experts for comment and will update this article if we receive a response.
Oxytocin
Several articles on the subject suggest that another hormone, oxytocin, affects one’s sleep-wake cycle. Oxytocin, often referred to as the “love hormone,” is a neuropeptide produced in the hypothalamus and released by the pituitary gland. “People in romantic relationships tend to have higher levels of oxytocin, a hormone associated with pair bonding,” Madeline Sprajcer, a psychology lecturer at Australia’s Central Queensland University, told Newsweek, adding that “It also appears that oxytocin can have a positive impact on our sleep.”
Oxytocin has been shown to make people fall asleep more quickly and rest more efficiently, with an increase in restorative REM [rapid eye movement] sleep episodes. This so-called love hormone is often released during sexual activity, particularly during orgasm. Oxytocin can be released by simply being in the presence of a romantic partner to whom you are strongly attached, Sprajcer said.
However, Newsweek’s article highlighted that “feeling sleepy around your partner is not a foolproof indicator of a happy relationship.” Emre Selçuk, an associate professor of psychology at Turkey’s Sabanci University, told Newsweek that “the calm and quiescent state that partners instill almost borders boredom,” underscoring that “the feeling that there is nothing else to do or to share with your partner can make you sleepy in their company.”
In an article titled “Why do I get sleepy around my partner? A therapist’s take,” NOCD therapist April Kilduff explained that “Studies have found that people in relationships tend to have higher levels of the hormone oxytocin than those who are single”:
This hormone, which is sometimes referred to as the “bonding” or “love” hormone, is important for building connections between human beings. Our brains naturally release more oxytocin after being touched, or through positive interactions with others. So it’s no surprise that people in good relationships tend to have higher levels. Oxytocin is also thought to alleviate stress and promote calmness. As a result, this may translate to feeling more relaxed and even sleepy when you’re with Your Person versus when you are alone.
There’s even research showing that sleep in general is better with a partner, which might play a factor. For example, a study at the University of Arizona found that adults who shared their bed with a partner or spouse reported better quality sleep than those who slept alone.
It could even be something in your partner’s scent that lulls you to bed. Yes, really! There’s evidence that being exposed to your partner’s scent might help you sleep better than nights spent without the scent.
Feeling Safe and Other Factors
Tasha Bailey, an accredited psychotherapist and author, told Glamour UK that “when we feel secure and comfortable with a partner, it can activate our body to feel so safe that we might fall asleep”:
The feeling of safety activates the parasympathetic part of our nervous system (which is the part that is in charge when we feel relaxed). Our pupils dilate, our breath gets deeper and our heart rate drops as our body slowly unwinds. This means that our body is preparing itself for rest, which is why we might find ourselves falling asleep easily with our partner.”
Bailey also explained that “if we don’t feel safe with a partner, our fight-or-flight sympathetic nervous system can be activated. This can leave us feeling on edge, anxious and too hyper-vigilant to be able to relax,” adding that feeling sleepy around a partner could mean someone feels safe and protected:
Feeling sleepy around your partner can be a great sign that you trust this person enough to fall asleep in their presence. If we think back to pre-historic times, our ancestors could only fall asleep in places and with people where they were safe and out of danger. So saying that we can fall asleep in the presence of a partner, means that we feel safe and protected.
Similarly, Kilduff said that “if you’re a little bit tired or it’s the end of the day, there’s a certain element of safety that could make it easy to feel sleepy around your partner,” adding, “It could even be as simple as the fact that you mostly tend to spend time with your partner at the end of a long workday, which would naturally coincide with your circadian rhythms — the internal body clock that dictates your sleep cycle.”
In closing, it is worth remembering that tiredness is a natural response to a lack of adequate sleep and isn’t necessarily related to the dynamics of a relationship. Therefore, sleepiness around one’s partner can also be attributed to factors such as sleep deprivation, stress, irregular sleep patterns and overall lifestyle choices. Moreover, certain sleep disorders or medications can lead to excessive daytime sleepiness, regardless of the situation or company.
