If you can complete this viral breath test it means your lungs are healthier than 95 per cent of the population…

A viral breath test claims that if you hold your breath for 60 seconds, you have better lungs than 95 percent of the population.

Such breath tests have taken social media by storm, with some claiming that those who can last even 40 seconds have ‘military-grade lungs’.

One of the latest offerings from the trend was Gideon Horner, a “breathwork” specialist, posted to Instagram.

In a post touting the benefits of breathing exercises for anxiety, Mr Horner is seen holding his breath for a minute as a timer ticks from A to B.

Before the challenge, he says: ‘If you can hold your breath from A to B, you have better lung capacity and CO2 tolerance than 95 percent of the population.’

It is unclear where Mr Horner got these figures from, but a large number of people struggled to meet the challenge, with some claiming they had almost been sent to an ‘early grave’ or that they had ‘seen their grandmother’ while they tried that.

Others, however, claimed to belong to this coveted 5 percent group.

‘I did it without any problem. I could have gone longer. I’m 78,” wrote one successful one.

‘I’m 51 and I almost didn’t make it! Those last 5 seconds!’ wrote another.

However, breathing capacity varies greatly from person to person and is not considered by doctors to be a good indicator of overall lung health.

Research has shown that the average person can hold their breath for between 30 and 90 seconds, although this varies.

Factors that influence this include age, smoking status, general fitness and, crucially, tolerance for discomfort.

It is the latter that means that doctors do not typically consider a person’s ability to hold their breath as a good indicator of respiratory health.

Although it was used as a measure of physical fitness during World War I, experts began to realize that it was not a good measure of physical health.

This is partly because people may train to hold their breath and tolerate their body’s discomfort for longer on oxygen, clouding any results.

As such, modern medical practitioners typically use something called a spirometry test to measure the health of a person’s lungs.

In these tests, a person has a clip on their nose and a tube in front of their mouth.

They then breathe only through the mouth and the amount of air they can inhale and exhale is recorded by a machine.

This is used to see if a person is collecting enough oxygen with each breath.

While humans, such as free divers and military personnel, can train themselves to hold their breath for long periods of time, with the world record approaching 25 minutes.

But as a challenge, holding your breath for a long time is not without risk.

People who suppress their natural desire to breathe may eventually faint, causing physical harm from falling to the ground, as well as possible seizures and even brain damage.

When a person holds their breath, not only is the flow of life-giving oxygen stopped, but also the exhalation of carbon dioxide (CO2)

This CO2 begins to accumulate mainly in the blood-brain barrier, a network of blood vessels and tissue that serves as a protective layer along the inside of the brain.

This can cause a drop in the delicate pH balance of the blood, causing the brain to send an urgent signal to the lungs to breathe.

Savvy social media users have also theorized that such breathing problems aren’t just about helping people measure their lung capacity.

Instead, they suggest that such posts are about increasing engagement, as viewers stay on the post for the entirety of the challenge, albeit for 40 to 60 seconds, and then read the comments to see how they compare.