If you held me for too long, you would die. What am I?

Answer: breath

More What am I ? with answers

More What am I ?

If you look you cannot see me. And if you see me you cannot see anything else. I can make anything you want happen, but later everything goes back to normal. What am I?
If you lose me you may cause people around me to lose me too. What am I?
If you throw me out the window, I'll leave a grieving wife. Bring me back, but through the door, You'll see someone giving life. What am I?
In a tree you'll find me moving slow as can be. My name is a sin but from them I am free. What am I?
In my life I must bare, my bloodline I must share. What am I?
In prison I will be found, But I’ll never be in court, Unless there’s more than one. What am I?
In the ground I am nothing, but give me time and I'll be something. What am I?
In the light, I may reflect. In the dark, I'm cold and wet. What am I?
In the morning I sing on feathered wing. I soar through the air without a care. What am I?
Island hello. What am I?
It can be said: To be gold is to be good; To be stone is to be nothing; To be glass is to be fragile; To be cold is to be cruel; Unmetaphored, what am I?
It comes only before, It comes only after, Rises only in darkness, But rises only in light. It is always the same, But is yet always different. What am I?