All you need to know about crying
All animals produce tears in some form or another, but did you know that humans are amongst the only species to produce tears because of our emotions?
Babies use their tears as a form of communication, before they've learned to talk or express themselves more clearly. But in adults, the purpose of crying is a little more complex. So, here at BBC Bitesize, we've taken a look into the science behind crying, to answer some of the biggest questions around:
- Why do people cry?
- Is crying good for you?
- Why do we cry 'happy tears'?
- And how can our tears be influenced by TV shows and onions?
Why do people cry?
There are three main types of tear we can produce: emotional tears, basal tears and reflex tears. When we talk about crying, we're usually referring to emotional tears, which are produced when we feel sad, frustrated, angry, overwhelmed and even happy. Reflex tears are produced to flush the eye of irritants, like dust, whilst basal tears are produced to keep the eye moist throughout the day.
Almost every creature with eyeballs produces basal and reflex tears, but emotional tears are unique to humans. Why we produce them remains something of a mystery, but researchers have proposed several explanations.
Some research suggests that we produce emotional tears when we feel helpless or overwhelmed, as a way of attracting help or support from those around us. This even applies in situations where we cry tears of joy, with the emotion being so extreme we begin to feel overwhelmed by it.
Other research implies that crying can help to lower stress levels and bring us back to emotional equilibrium. But how exactly does that work? Read on below to find out!
Is crying good for you?
If you've ever been comforted in a flood of tears, chances are you've heard the phrase "cry it all out". It is often believed that crying can help purge the body of toxins and negative emotions, helping you to feel better when the waterworks subside.
It might sound like a tall tale, but there's actually some truth to it, even for emotional tears. Research suggests that crying, especially in an emotional context, activates the parasympathetic nervous system. Also known as the 'rest and digest' system, the parasympathetic nervous system decreases the rate of energy expenditure and calms the body down. Activation of this system suggests that crying helps calm us during intense emotions, slowing heart and breathing rates.
Why does cutting onions make people cry?
Chopping onions causes the release of reflex tears, which are very different from emotional tears, and triggered by exposure to irritants.
When you chop an onion, it produces an irritating gas known as Propanethial S-oxide. This turns into sulphuric acid when it comes into contact with the water layer atop your eye, which, in turn, releases tears as a defence mechanism to flush the irritant out.
The strength of your reaction can vary based on a number factors, including the specific type of onion you're chopping. To reduce tears when chopping onions, work in a well-ventilated area, use a fan, or wear protective goggles.
Why do people cry watching TV?
Whether it's the final season of your favourite show, or the deluge of sentimental Christmas adverts, there's all sorts of things on TV that can make us cry - but why?
Well, simply put, it's the power of storytelling. When it comes to the final season of a show, such as Stranger Things, the tears are perfectly natural. For some, the story has been ongoing now for 10 years, with characters coming to feel more akin to an old friend than a televised fiction. And just like real life, goodbyes in fiction are always hard, whether that's the end of a film or a TV series.
Creating characters and worlds that people become emotionally attached to is no mean feat, but in doing so, a strong emotional bond is created between the story and the audience, allowing creators to manipulate this audience into feeling emotions like loss or sadness.
Tearful TV ads serve a similar purpose, used to create an emotional attachment between a viewer and a brand, with the hopes of influencing your future purchases.
Some research has shown that our behaviour is more influenced by our emotions than logical reasoning, you may have heard the term 'heart over head'. Advertisers have sought to tap into this with a strategy of 'sadvertising', creating an emotional connection to a particular product or brand. Many TV ads don't even show products, instead hoping to create an emotional impact on the viewer. For example, if you watch the John Lewis Christmas advert, you might not come out knowing what John Lewis actually sell. Despite this, however, they're one of the first brands you'll think of when the Christmas shopping season rolls around.
Another reason for this, is the chemicals our body releases when we cry. Crying emotional tears releases endorphins, sometimes known as feel good hormones, into our body. By tapping into our tear ducts, creators and brands can create a link between their show or product and our personal wellbeing, in the hope we will be more likely to consume it further in the future.
Why do people cry when they're happy?
Dr. Ad Vingerhoets, a professor of Clinical Psychology at Tilburg University in the Netherlands, suggests that we cry when we feel helpless or overwhelmed.
Speaking to CrowdScience, on BBC Sounds, he suggests this serves as an explanation for happy tears (or 'tears of joy' too). While we don't tend to associate feeling happy with helplessness, feelings of joy can still be overwhelming. He suggests happy tears come as a result of extreme feelings of happiness that we otherwise don't know how to process.
He also suggests that emotional tears come about when we feel a strong need to connect with those around us. As such, happy tears may begin to flow when we feel a joy so potent that we simply have to share it with others, as opposed to holding it inside for ourselves.
