love, sex, marriage, love sex & marriage, biology of love, biology

There is so much written about love, sex and marriage, but just how much do we actually know about it all? Love is not a tangible thing, but we certainly know when we experience it, therefore, it’s an emotion. So lets start there: How many of us know where love actually comes from and how it’s linked to sex and marriage?

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Science has taught us a thing or two about love and it has been a hot topic of inquiry for years. We’re going to focus primarily on the biological model – psychological and evolutionary models have interesting perspectives, yet to understand love, sex and marriage from a couples perspective, the biological model will be the most helpful.

Now, the biological model sees love as a drive similar to hunger and thirst. A leading expert in love has identified partly overlapping stages of love which include lust, attraction and attachment. These are influenced by different chemicals in our bodies and each have influence on the stage of love experienced.

The first stage is lust – this has a lot to do with sex. Lust is heavily dependent upon testosterone and estrogen hormones, but unfortunately this stage rarely lasts more than a few months, and also why it’s difficult to sustain long term. While married couples may experience urges of lust, upon first contact is generally the time when it is the strongest.

The next stage is attraction – this is the stage people talk about when they mention an addiction to love. As this stage takes hold, neurotransmitter hormones such as dopamine, norepinephrine and serotonin act to stimulate the brain’s pleasure centre.

Interestingly, these hormones are released by amphetamines and produces a similar effect on the central nervous system. This includes that racing heart feeling, loss of sleep and appetite, plus provides that intense feeling of excitement. Anyone who’s ever been in love would admit to it being an awesome feeling.

Unlike lust which can be generic, attraction is much more personal and is based on desire for that special someone. Research believes it develops out of lust in the form of commitment to that person. It can last as long as three years and may explain why some marriages are short lived. Others like the feeling so much they avoid the later stages of love and instead have a string of short lived passionate flings.

The final stage of love is the foundation of long-term marriages or relationships and is based on attachment. Hormones vasopressin and oxytocin play a vital role and are said to be found in higher levels within individuals in long-term marriages or domestic partnerships.

While oxytocin has been labelled the ‘love-hormone’, some studies have found a link with domestic violence. In people predisposed to violence, which may involve prior bonding and attachment difficulties, increased levels of oxytocin may trigger an incident. This may be why abusive relationships usually start well and have few or no signs of things to come. As the levels of oxytocin increase, along with the desire for bonding, the propensity for abuse emerges.


Akin to love, sex is also a drive like thirst and hunger. According to research, it’s primarily based on sexual desire, which is a synonym for lust. There’s been recent findings by neuroscientists on brain areas associated with both love and lust – love is highly associated with areas which habits originate, while lust evolves in the pleasure centre. This is also associated with our need for food and sex.

It seems that although sex and love are basic human drives, they derive from two separate needs. This is an important fact for couples in long-term relationships: Despite the ‘love’ which develops over time, sex plays a different role. This is perhaps why some couples can love each other deeply, but have different requirements when it comes to sex.


Marriage is entirely different from both love and sex and has no biological basis. The link to sex is based upon approval in many cultures and religions, while the link with love has developed alongside partner selection.

How marriage is linked to love is more complicated than simple. As we know, the attachment stage of love is biologically where habits form and many marriages resemble a habit, rather than filled with lust or passionate attraction. Elderly couples resemble this in their desire to remain together throughout a lifetime.

Things get habitual over time. This is the stage we’d all prefer to avoid, particularly in the bedroom! However our biology is working against us. Understanding this factor we acknowledge how marriages or long-term relationships enter a rut, in which the love may be strong and enduring, but boring. This can explain how tension forms and why people try to put that spark back into a relationship or opt to enter a new one.

This is also why people start affairs – they crave that excitement experienced during the initial stages of their marriage or relationship. This is also why affairs remain affairs, as many won’t leave their spouse because they do really love them. I did say it was complicated!

For others who prefer to remain faithful, arguing because they enjoy makeup sex, or initiating some other form of distancing, provides an avenue to re-ignite the spark. The trick is to find healthy alternatives to keep this attachment stage from getting habitual.

So there you have it: Love, sex and marriage is a very interesting topic. Understanding how biology affects love and relationships can help couples to overcome some of the problems that arise. Knowing in advance that things will get habitual over time is also a great incentive for couples to form habits which excite, rather than add to the boredom!

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