Hormones and Transmitters

Oxytocin and Lego Technic

22 June 2017

This post is also available in: Dutch

stylized image of a toy car made of lego blocks

Oxytocin makes you happy. This is what you read in newspaper headlines and websites. When you cuddle a baby, oxytocin is produced. Oxytocin induces trust. Oxytocin is good for improving social interactions. Oxytocin plays a central role in maternal attachment, friendships and romantic interactions, as it does with sexuality. Oxytocin the cuddle hormone, Oxytocin the love hormone. Oxytocin makes for monogamy.
But oxytocin is not a cuddle hormone. That is simply not possible. If it were, we would have heaven on earth: we would just have to find out how we could stimulate oxytocin production in the whole population and that’s it! How then do these wonderful properties of oxytocin make it to the news? You would expect that scientists had found evidence for all of this. Well, scientists have shown that oxytocin does play a small role in bringing about these processes – under certain circumstances. I will use a metaphor to show what this means.

Oxytocin is like an “eight”

My grandchildren play with Lego Technic (as does my 40-year old son). Imagine a Lego car with an advanced steering system. Apart from all sorts of complicated pieces this system contains the classic, simple bricks with 8 knobs, let us call them the “eights”. If you remove the “eights”, then the car does not steer very well. So the “eights” are the steering pieces! The driver’s seat in the car stands on four Lego pieces, of which one is an “eight”. If I remove the “eight” then the seat sags and is crooked, and the driver cannot sit comfortably. So the eight is the seating piece! Are the eights now steering pieces or seating pieces? Everyone can see that this is a ridiculous supposition.
Calling oxytocin the cuddle hormone is just as ridiculous. Because a hormone is a molecule, and it functions in the human body just as an “eight” does in a Lego car. It is a necessary component in various functions, but is not THE component for carrying out that function.

Complex functions

Cuddling, being happy, trust, social interaction, sex, friendship are complex functions and behaviours. Millions of different molecules are required for each behaviour or function, and no single molecule can do this on its own. It is however possible to change something in a particular function or behaviour by working on one molecule, in this case with oxytocin. And this can even be useful. Oxytocin is administered to facilitate shrinkage by contraction of the uterus after a delivery, or if the milk ejection reflex does not work properly. These are relatively straightforward functions of oxytocin. In complex behaviours such as cuddling, you cannot expect that working with oxytocin (for example, by using a nasal spray) will have much effect. This is demonstrated by experiments which find an effect. The effects are statistically significant, but of almost negligible size. Renowned researchers have their doubts whether these experiments are credible at all.

Oxytocin an aggression hormone?

The problem with tinkering with oxytocin is far more serious. The effect of oxytocin depends on external circumstances. It can reduce anxiety and aggression against people who belong to the same social group, but on the contrary increase anxiety and aggression against other people. Although this has not been researched or proven, I expect that this is true for all the functions and behaviours mentioned in this article. Some people with psychiatric disorders, including autism and schizophrenia, have set their hopes on oxytocin. Sadly, I can predict that oxytocin is not going to be the cure for these disorders. It may on some occasions be able to alleviate some unpleasant or severe symptoms. But on other days, in different circumstances it will aggravate the very same or other symptoms.

A small link

So are we better off forgetting about oxytocin? No, I do not want to imply that. There has been worthwhile research into the role of oxytocin, for instance in autism. It is quite possible that oxytocin plays a role here, and that accurate and detailed research demonstrates that in some cases tweaking oxytocin at some moments works beneficially. To continue with the metaphor: you first need to know the exact position of the wrongly placed Lego “eight”, and how you can set it just right at precisely the right place. And we are a long way away from there as far as oxytocin and autism are concerned, if it is at all possible.

Food and drugs in advertisements

The moral of the story is: one molecule in our body is never responsible for complex behaviour. This is true not only for oxytocin, but for all molecules. Perhaps you should watch out for advertisements claiming the specific health benefits of one particular chemical – a medicine, a food supplement, a hormone, a vitamin. That one chemical can never help for that health problem, unless you just happen to have a specific lack of that specific substance in your body. But this is something you should have tested by a doctor first, because in that case we are talking about a specific and rare medical condition.

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