Hiccups: a guide to common causes and quick relief

What are hiccups?

Most of us have had hiccups at some point in our lives. We usually see them as brief annoyances that come and go, rarely pausing to consider why they happen.

Dr Vian Miran, Hola Health, Victoria, Australia, says that for something so widespread, it's surprising how little thought we give to understanding what hiccups are, and how to prevent them. Instead, we often just wait for them to pass and quickly forget about them afterwards.

She describes hiccups as an involuntary contraction of your diaphragm - the muscle that separates your chest from your abdomen and is essential for breathing.

"When your diaphragm contracts unexpectedly due to a spasm in your phrenic nerve - the nerve which controls your diaphragm - air is drawn in through your mouth," Miran explains. "However, this influx of air is suddenly halted by a tightening of your vocal cords, which makes that peculiar 'hic' sound."

Having a sudden bout of hiccups isn't generally something to worry about. However, understanding what causes them can help reduce your likelihood of getting them.

Swallowing air, drinking fizzy drinks or alcohol, eating spicy foods, and sudden temperature shifts can all induce hiccups.

"In some cases, long-lasting hiccups can be a symptom of underlying conditions, either psychological or physical," says Miran.

Hiccups usually go away on their own within two to ten minutes. However, according to Miran, a simple technique developed by neuroscientist Andrew Huberman is widely recognised as an effective way to stop hiccups quickly.

"These pressure changes hyper-excite and then over-relax the phrenic nerve, stopping the spasms that cause hiccups," says Miran.

She adds that several traditional methods are used to stop hiccups, but none are as effective as the above.

"Most hiccup resolution methods attempt to affect your phrenic nerve through indirect interactions," she explains. "For example, a common method of breathing into a bag aims to re-inhale carbon dioxide, thereby adjusting your blood’s carbon dioxide levels and potentially changing your breathing pattern.

"This change can then disrupt the spasms in your phrenic nerve. However, there are a lot of “ifs” in this method."

As mentioned, hiccups typically resolve quickly on their own and usually don't signal any underlying health issues.

However, Miran advises that if your hiccups persist for more than 48 hours, you should talk to your doctor, as this might be a symptom of a more serious cause.