Some people smell human, while your partner may smell like a Parisian pastry shop. And it can take great restraint not to press your nose into their neck and inhale.

BO? It doesn’t exist for them. And even after a 30-degree run or yet another forgotten swipe of deodorant, they somehow still emerge smelling like fresh rain.

For me, smell has always played a powerful (subconscious) role in attraction. My boyfriend’s natural scent – earthy, warm, with hints of honey – is incredibly soothing (it sounds weird, I know). But there’s science behind it, okay.

To most, he probably smells like any other human, but to me, his scent signals something deeper… we’re compatible partners, genetically, of course.

And yes, the data backs this up. It turns out, our sense of smell plays such a powerful role in choosing a partner that Dr Martha McClintock, one of the world’s leading experts on pheromones and chemosignals, says women can “smell differences as small as a single gene.”

Yeah, forget about trusting your gut – try trusting your nose.

Researchers at the University of Chicago have also discovered that women’s scent preferences for certain men may actually be inherited from their fathers. Yep, attraction really can run as deep as your genes (how sexy!)

In other words, your biological attraction radar might be partially programmed by your father’s immune system and how your body reacts to the subtle chemical signals (AKA smells) that hint at genetic compatibility and a healthy immune system. Essentially, we’re naturally drawn to the scent of men whose genes differ from our own.

And this isn’t the only research backing it up. Cue the “T-shirt test.”

In this study, 44 young, healthy men from the University of Bern in Switzerland were given T-shirts and instructed to wear them to sleep for two consecutive nights, avoiding deodorant, cologne, spicy foods, and anything else that might mask their natural body odour. Afterwards, women were asked to smell and rate the shirts based on how attractive they found the scent.

The study found that the women favoured T-shirts worn by men whose Major Histocompatibility Complex (MHC) immune system genes differed most from their own. MHC genes play a key role in helping the body recognise and fight off infections, bacteria, and parasites. This pattern suggests we may be biologically wired to sniff out partners with complementary immune systems.

If you’re wondering why this matters, it’s because these genetic differences are believed to produce healthier, more resilient offspring – think of it as nature’s very own matchmaking tactic to boost the survival of the human race.

But don’t put all your faith in this odour-matchmaking phenomenon just yet. Hormonal contraception can flip the script on attraction, changing how your nose (and brain) respond to potential partners.

Dr Sarah Hill, Associate Professor of Psychology and expert on hormones and behaviour, puts it simply: “Hormonal contraceptives alter the natural hormonal rhythms that guide women’s scent preferences, essentially rewiring what they find attractive.” Instead of sniffing out genetically different scents like their biology intended, women on the pill often prefer genetically similar ones.

Dr Sarah Hill explains that sometimes when women stop taking the pill, their hormones often return to their natural rhythm,  and, suddenly, the once-delicious scent of their partner can sometimes become off-putting.

While it may feel like cause for alarm, this is just your hormonal mate radar doing a reset, and it’s definitely is not a sign to dump your long-term partner on the spot. Just because your MHC genes aren’t perfectly aligned, it doesn’t mean you aren’t compatible in other, arguably more important, areas.

If you’re genuinely curious about finding a partner who’s both nose-approved and genetically compatible, there is an actual service for that. Smell Dating is an online matchmaking experiment that pairs you with a date based on, you guessed it, your body odour.

It’s billed as “the first mail odour dating service,” and the concept is simple: ditch the dating apps and let your nose decide. You’re sent a plain white T-shirt to wear for three days – no perfume, deodorant, or anything that might cover up your natural scent. Then, you simply post it back and await a curated selection of other people’s worn T-shirts to sniff. From there, you choose the scents that most appeal, and if the feelings are mutual, you have yourself a match.

It’s matchmaking stripped down to pure chemistry – literally.

So yes, being drawn to someone’s scent can be a sign of genetic compatibility – but don’t let that be the driving force of your connection.

My advice: use all your senses. And if they just happen to be a walking green flag who smells better than freshly cut grass and puts your nervous system at ease, I’d say that’s a match.