Why do people get the hiccups and how do you get rid of them?

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!

Why do people get the hiccups and how do they get them? And how do you get rid of them too? – Noah, aged 10, Brunswick East.

Hi Noah! Those are really great questions. We all get hiccups, but most of us don’t think much about them.

Let’s start with what happens when you hiccup.

There is a sheet of muscle under your lungs called the diaphragm. It’s very important, even though you don’t normally know you are using it. When you breathe in, this muscle pulls your lungs so they can fill up with air.

Read more: Curious Kids: Why do tears come out of our eyes when we cry?

When you get hiccups, you are getting involuntary spasms in this muscle. This makes you take in air really fast, like a super quick breath. The air rushing in shuts your vocal folds, causing the “hiccup” sound. Sometimes you hiccup once, other times for a few minutes. In very rare cases, they can last a very long time. The world record is more than 60 years!

Hiccups are usually started by eating or drinking too much and too quickly – particularly with fizzy drinks. This can stretch and upset your stomach, causing hiccups as the diaphragm contracts. Sudden changes in temperature or getting too excited might trigger this too. These hiccups are normally over quickly. However, if someone has an illness in their brain, nerves or tummy, they might get hiccups often or for a long time.

So how do you make them go away? Do you hold your breath? Drink water upside down? There are lots of stories about what fixes hiccups. Most hiccups go away on their own so it’s hard to say if these tricks work. They could just be a distraction, but they also might help reset the nerves causing the hiccups. A big study comparing all the different treatments found that none of them actually work.

Read more: Curious Kids: How do glasses help you see?

Why we hiccup is a very good question, and the answer is we don’t really know.

Hiccups serve no obvious purpose. It is possible they did something in our distant evolutionary relatives and never left us. Tadpoles have a hiccup reflex which helps keep their lungs safe while they transition from breathing underwater. So our hiccup reflex might be from our amphibian ancestors.

We all start our lives inside the liquid of our mum’s womb. So another theory is that hiccups stop us from breathing in the womb, or might be a way to train breathing muscles after birth.

The short answer is we know what hiccups are, but we don’t really know why they happen. The good news is that mostly you don’t need to worry about how to make them go away!

Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. They can:

* Email your question to curiouskids@theconversation.edu.au * Tell us on Twitter by tagging @ConversationEDU with the hashtag #curiouskids, or * Tell us on Facebook