Similarly, when you enter a room, such as a restaurant, bar, office, or conference room, you probably do a quick scan of the room. If someone seems physically attractive to you, your eyes may linger on them, or keep going back to them, and you may find yourself interested in what they’re doing or saying. Physical attraction is often instant, and it can contribute to feelings of excitement, increased energy levels, and craving for physical connection upon seeing someone for the first time. Instant physical attraction and ensuing emotional response are contributing factors to what people call “love at first sight.” This article explores some of the factors that contribute to physical attraction, the signs of physical attraction, and the importance of physical attraction in relationships.

Factors That Contribute to Physical Attraction

These are some of the factors that play a role in physical attractiveness:

Facial features: According to a 2015 study, facial features and facial symmetry are the most important determinants of physical attractiveness. Physical dimensions: Research studies also show that apart from facial features, other anthropometric factors such as physical dimensions and ratios play a role in physical attractiveness as well. Facial expressions: The face typically plays the most important part in social interaction, making facial expressions another important component in physical attractiveness, according to a 2021 study. For instance, the study notes that smiling signals intelligence and trustworthiness and increases physical attractiveness. Non-visual cues: A 2015 study shows that other non-visual cues such as voice and scent also contribute to physical attractiveness.

Evolutionary Factors

Evolutionary psychology has a controversial theory about physical attractiveness. It suggests that since physical attractiveness helps people attract mates, evolutionary factors play a role in what people consider attractive. Evolutionary psychology studies note that physical features and dimensions that suggest youthfulness, physical health, mental and emotional well-being, strength, and fertility are considered physically attractive, since those are desirable qualities in a mate from a biological and reproductive standpoint. For instance, evolutionary psychology studies conclude that a body mass index (BMI) and waist to hip ratio (WHR) within a particular range of those scales may be considered more attractive than a BMI or WHR outside those ranges. According to evolutionary researchers, this is because having too much body fat is associated with negative health outcomes such as heart disease, diabetes, and restricted movement; whereas, not having enough muscle and body fat is linked to a lack of strength and reduced fertility and child-bearing ability. However, there is not always a correlation between what is the healthiest physiologically speaking and what people find the most attractive.

Sociocultural Factors

Factors such as society, culture, and historical period can also play a role in determining what’s considered attractive and unattractive. In other words, if a culture favors certain body types over others, individuals can be affected by these preferences. People may internalize these standards and pursue them, sometimes to the detriment of their health or well-being. For instance, they may pursue a BMI that is below what is considered healthy, in order to meet sociocultural standards of size. One study found that participants perceived as more attractive women with low and physiologically unhealthy BMIs compared to women with healthy BMIs. Another study found that participants from urban areas thought images of women with lower BMIs were more attractive compared to participants from rural areas who felt women with higher BMIs were more attractive. Weight stigma and the thin ideal can play a role in determining what people view as attractive and unattractive regardless of what is physiologically healthy.

Signs of Physical Attraction

Physical attraction is characterized by physiological changes in the body, such as a release of the chemicals dopamine and norepinephrine in the brain, says Dr. Romanoff. “Attraction also activates the orbitofrontal cortex of the brain, which is the part of your brain that processes sensory rewards.” These physiological changes can trigger emotional and behavioral changes. These are some of the signs of physical attraction, according to Dr. Romanoff:

Smiling when around the person Maintaining prolonged eye contact with them Feeling nervous at the prospect of interacting with them Unconsciously mirroring their body movements, expressions, speech, and postures Having reduced appetite and difficulty sleeping Feeling unsteady, ecstatic, and animated

Physical Attraction and Relationships

Physical attraction is an important component in romantic relationships. It is often the starting point of relationships, helping people connect with each other and build an emotional attachment. Physical attraction also helps people maintain relationships. According to a 2015 study, being physically attracted to one’s partner is linked to greater marriage satisfaction and longevity. However, relationships shouldn’t be based on physical attraction alone. Couples should have a strong and widespread foundation for their relationship—this includes an alignment of values, goals, and priorities, says Dr. Romanoff. “If partners are not connected in these other realms, their physical attraction might not be able to sustain a more serious relationship.”

A Word From Verywell

Physical attraction is often a primal, instinctive reaction to another person, based on factors such as their appearance, expressions, voice, and scent. While physical attraction is one aspect of being in relationship, it is also important to consider and build upon shared values such as trust, compassion, respect, and honesty.