What happens when we fall in love?

Siski Green / 19 October 2018

While the concept of love changes over time, within the first few months of falling in love with someone, your body will behave in the same way it always has.



You look forward to seeing your new partner, you might even get butterflies in your stomach when you think about it. When you kiss, you get tingles all over and your knees nearly give way.

But, you think, surely I’m too old for this kind of puppy love? Maybe the butterflies are just indigestion, the tingles and weak knees down to that new medication or some health ailment?

Fear not, you’re likely as healthy as ever, you’re just experiencing the classic physical response to falling in love.

It doesn’t take long for your body to start sending you the signals that you and the object of your affection are falling head over heels. In fact, you can start experiencing all the feelings of love well before the average three months that it takes us to realise we’re in love.

That figure doesn’t change as you get older either. According to a survey undertaken by GalaBingo.com, retirees are no slower to fall in love than their younger counterparts. The research revealed that if we are going to fall in love, it takes us around three months to feel it. It might take us a little longer to say it out loud, however, with one in four people saying it takes another three months after that before they can share those three little words.

Try Saga Dating

  • Create your free online dating profile in under five minutes
  • Find your match with our unique two-way matching process
  • Protected by the Online Dating Association

Join Saga Dating today

The physical signs of love

While the concept of love changes over time, within the first few months of falling in love with someone our bodies behave in similar ways...

Lust is in the air

Whether or not you’ve already had kids, or whether your body is capable of producing babies, your body is still primed for seeking out a partner who’ll produce ‘good’ healthy offspring. Like it or not, your nose leads the way in this.

In a Swiss study, researchers asked a group of men to wear the same T-shirt over a period of days. The clothing was then put in different boxes and women were asked to rate the attractiveness of a man in a photo while smelling the shirts. Regardless of which photo they were shown, the women rated certain T-shirt smells as more attractive than others. What does this mean? That we trust our noses to tell us when a man might be a good match or not.

7 ways to increase your libido

Dieting becomes really easy…

What a handy coincidence – falling in love also makes it easier to keep excess weight off! Loss of appetite during the initial stages of love is common and it’s all down to dopamine. This chemical is released and it dampens your desire for food, leaving you feeling giddy and somewhat euphoric too.

Sleeping does not

In the first few months of falling in love, your serotonin levels fall a little. Usually described as the feel-good hormone, it’s also responsible for keeping you calm… and sleepy. With all that dopamine and norepinephrine coursing through your veins, your body isn’t set up for sleep right now. Enjoy the extra energy and use it to spend more time with your new partner!

All this giddy energy initially comes from phenylethylamine, which triggers the release of dopamine and norepinephrine, and guess what? This is the exact same chemical process you’ll experience when you take a ride on the big dipper, watch a thrilling film, or go paragliding.

How to get through day after no sleep

What’s next?

Your body can’t sustain this level of euphoria for too long. Aside from eating and sleeping less, your body is in a state of alert and that can be draining in the long-term, and researchers believe the limit is two years – by this time your body is accustomed to the raised levels of high-making hormones and begins to calm down.

So, this is when your body ensures a longer-lasting relationship by releasing more oxytocin. It helps calm you but keeps you feeling close and bonded to your partner.

It does even more than that too – according to research from the University of Zurich, couples who were given oxytocin before being asked to resolve a conflict were more likely to address the topic in a positive, friendly manner.

Is it really love, though?

According to the GalaBingo survey, one in four Brits have said I love you to someone and not meant it. So how can you be sure what you’re feeling is the real thing?

'There’s no such thing as a love ‘standard’,' says sex therapist Dr Ian Kerner (goodinbed.com). 'For one person, being in love will require commitment from the other person, time spent together and so on, for another, it may be something they experience fleetingly or even from a distance.'

For most people who say ‘I love you’ when they don’t mean it, it’s a case of doing it to avoid the other person’s feelings or in order to avoid addressing the issue of why they don’t.

'People may want to love the other person they way they love them, but they’re just not feeling it in the same way,' says Kerner. 'There are situations where a person seems ideal in every way, attractive, fun to be around, similar life goals and yet… that overwhelming desire to want to be with him or her just isn’t there.' That, sadly, is when love can feel really cruel.

'This lack of ‘that certain something’ may well be down to chemistry,' says Kerner. 'Sexual attraction is based on many things but genetics plays a large role.'

It’s all down to your genetic HLA, or human leukocyte antigen complex. This is what steers your immune system, helping your body to identify bacteria and viruses, versus healthy cells in the body. Research published in Nature magazine found that each person within happy couples had different HLA patterns to their partner. The researchers say this different pattern ‘correlates with sexuality and enhances the desire to procreate.’ 

While you may have zero desire or thoughts of procreation, your body is primed to ‘think’ otherwise and is still seeking that perfectly different HLA partner for you. So, if there’s simply no ‘chemistry’, you can blame your genes.




The opinions expressed are those of the author and are not held by Saga unless specifically stated.

The material is for general information only and does not constitute investment, tax, legal, medical or other form of advice. You should not rely on this information to make (or refrain from making) any decisions. Always obtain independent, professional advice for your own particular situation.