We take 23,000 breaths a day; trying to get oxygen to our brain and cells.

Oxygen is essential to our survival.

But it's a only small percentage of what's in the air we breathe.

So what if there was more of it?

These are just a few of the things we'd be dealing with if the Earth's

atmosphere had double the amount of oxygen it has today.

What else would happen?

Our atmosphere contains about 20% oxygen and roughly 78% nitrogen.

Even though it's not the most significant part of our atmosphere, it is the most important.

90% of our energy comes from oxygen, with the rest being from food and water.

You wouldn't be able to watch this video without oxygen, you wouldn't be able to do anything.

That's because you wouldn't be alive.

And, not only is oxygen essential for humans, it's vital to all life on Earth.

Now, what would happen if the Earth had double the amount of this crucial element?

The first thing you'd notice would probably be those giant bugs.

Insects breathe through tiny tubes called trachea.

Scientists have theorized that if more oxygen were to enter these tubes,

insects like spiders and cockroaches would grow much larger.

About 300 million years ago, during prehistoric times,

Earth's atmosphere was 30% oxygen. During that time,

insects were much, much larger.

Dragonflies were the size of hawks, while some spiders were the size of small birds.

Doubling the Earth's oxygen levels would mean having

even more oxygen in our atmosphere than back then.

Our insects would be even more enormous.

Although these giant insects might scare the pants off of you,

you can feel better knowing that you'd have much more energy to outrun them.

With a higher oxygen level, you'd notice you that have much more energy.

The human endurance records of today would quickly

be shattered after everyone gets more oxygen in them.

You'd also be more alert.

More oxygen in your body, improves your circulation and increases your energy.

Humanity would see much less disease, and you'd call in sick a lot less.

Or, would you?

A type of infection-fighting immune cells known as neutrophils would occur more often,

keeping you healthier. You'd get a lot fewer colds!

You'd be like Superman!

Well, not quite.

The increased amount of oxygen your body is getting could also

lead to some serious long-term health problems.

With the increased levels of oxygen, humans would have an increased chance of oxygen toxicity.

This happens when humans are exposed to higher

oxygen levels than their bodies are normally used to.

Over time, this could lead to lung damage, poor eyesight and cells not being able to reproduce.

Having too much oxygen in your body creates free radicals.

These atoms look for other electrons to pair up with.

When this happens it can cause damage to your body and your DNA.

Oh yeah, and what about those crazy fires we mentioned?

Well, with more oxygen in the atmosphere

things would catch on fire more easily.

Generally speaking, when you can't start a fire it's due to the lack of oxygen.

With there being even more O2 the atmosphere think of how easy everything would catch fire.

Think California forest fires are bad?

Expect those to happen all around the world.

Even wet vegetation would have a chance at burning.

And as for the planet as a whole? Well for one, we'd have a lot more mass.

Oxygen isn't just in our atmosphere. It also plays a large part in the Earth's crust.

And with more oxygen the crust would be heavier,

making the lithosphere heavier than our atmosphere.

This would cause things to oxidize, including large bodies of water,

turning into hydrogen peroxide.

So, some good and some bad comes with this,

but luckily you can take a sigh of relief knowing that our atmosphere only has 20% oxygen.

And so far it's worked out pretty well for us.

But imagine if we had no oxygen?

That sounds like a story for another, WHAT IF.