Why are we attracted to some people but not others?

You see someone across a crowded room, and you're instantly attracted to them. What is that all about? And why can you read someone's words and swoon (like when they're messaging you on a dating app), but meet them in person and just feel the ick? In our Good Girls podcast, Mikayla and Siobhan explain the science of attraction. Warning: You might be weirded out.

Understanding attraction

There are six-ish types of attraction to consider, and they might not be exactly what you think they are:

1. Physical attraction - related to your desire to touch or be touched by someone. Not necessarily sexual but definitely intimate (you want to hold hands, hug, kiss, etc).
2. Emotional attraction - being into someone's personality or the things that make them "them". You want to learn more about them and understand them. You're hot for their soul. Interestingly, relationship experts think that if you can maintain a level of emotional attraction with someone, you're more likely to have a successful long-term relationship.
3. Romantic attraction - wanting to be romantic with someone, but not mutually exclusive with physical or sexual attraction. It's about the lovey-dovey, heart eyes, flowers and chocolates, romance side of things.
4. Sexual attraction - the desire to engage in sexual activity with someone. It's about arousal and lust, not necessarily being attracted to the way someone looks. This relates closely to physical and romantic attraction, but you don't have to have these in order to feel sexual attraction. Think of your celeb crush - you'd be happy to shag them, but you think you'd probably skip the relationship.
5. Aesthetic attraction - you're attracted to the look of someone. Their muscular arms, sexy tousled hair, hot bod, luscious lips... You appreciate how gorgeous they are, but you don't necessarily need to feel like you want to do anything more than appreciate the beauty.
6. Intellectual attraction - an attraction to someone's intellect which can overlap or blur with the emotional attraction. This is more about their thoughts, opinions, smarts, and expertise in an area that interests you - a connection on more of a brain level. This can often be the type of attraction people register first - you might hear someone speak (or read their words) and be interested in what they're saying, and then you register the physical, aesthetic, etc.

Mix and match

These attraction styles definitely mix and match, but when you want to be in a relationship with someone, you'll probably feel an amalgamation of all of these. Interestingly, though, psychologically, if you have a physical or romantic attraction to someone, you tend to perceive the other types of attraction to that person more highly than they may be in reality - whether you know anything about them or not.

So why the hell are we attracted to people?

Here's the biology: Because humans are animals, we have the same animalistic drive as every other animal in the kingdom - the desire to procreate is just hardwired in us. Possibly terrifying given the stage of life you may be at presently, but true. And in order to perpetuate our species, we need to procreate. That "thing" in us that drives us to continue to populate the earth isn't just a single characteristic. It's a combination of things. But mostly, it's about sexual attraction.

Obviously, the planet is overpopulated and we're not in a position of needing to keep pumping out babies. But biology cannot be stopped. Well, it can, but...

But wait, there's more

Smell is a big driver of attraction. We're not talking about expensive perfume, we're talking about your natural body odor, which relates entirely to hormones. When we like the smell of someone, we're liking their hormonal makeup. Studies have confirmed this - including studies that showed when women were at the most fertile part of their menstrual cycle smelled the best to men. Yep, this is kind of horrifyingly fascinating.

Taste is important too. Here's a fact you will probably want to run away after reading this: When we kiss, we transfer about 80 million bacteria into each other's mouths. There is a reason why this transfer of bacteria plays a biological factor in attraction. Researchers say that humans don't have strong olfactory skills (despite the above guff about smell being important), and kissing allows you to smell and taste a person, allowing us to evaluate their immune response which, again, relates to determining whether they'd be quality to have babies with. Kissing also boosts oxytocin (the love chemical), which boosts our attraction to someone too.

And there's our hormones. Estrogen and progesterone can make people smell different (remember, they're linked to fertility), and being in the most fertile phase of your cycle impacts a lot of things. You look different, you sound different, you smell different, and all of those micro-things are picked up on by our bodies and brains, affecting whether someone is going to be attracted to us and vice-versa. Our other hormones definitely play a part in attraction (testosterone, serotonin, dopamine, etc) too.

Blame it on our biology

Biologically we're more likely to be attracted to people who are like us. This comes from a tribal/community part of our monkey brain which reminds us that we feel safe with our own group. However, if our genetic makeup is too similar, we won't be successful with our potential offspring, so we need to ignore this monkey brain instinct and go for variety.

Attraction is subjective, but it's also pretty hard-wired into you. There's a lot you can't ignore because your monkey brain is telling you want to do. So this might help you feel better about choices you've made in the past - your rational, modern brain wasn't in charge. It was your monkey brain telling you to get with that bad boy who was super hot but treated you terribly.

So why are we attracted to whom we're attracted to? It's a mixture of evolution, throwbacks to our primitive ancestors that we brought along for the ride, and biologically hardwired responses to other humans. And it's all about procreating. You're welcome and we're sorry. Next time you spot someone across a crowded room and think, "They're a bit of all right!" know that your brain and body are hard at work trying to figure out how to keep our species alive, when you might just want someone to buy you a drink.