usage of head set will reduce the hearing capacity of ears

Well,based on what I've learned from my anatomy class,reduce hearing capability results when your ears are subjected to high volumes which disrupts the ability to determine balance with surroundings.If you like music and prefer to hearing it loud,you got to choose the correct earphones or headsets.As for headsets,try to get a loose one( there are a little bit of spaces between the headset and your ears) so that they are plenty of air that can move through in order for your ear to be relieved and maintain balance with external surroundings.

Yes, this is one of those things that we all know we shouldnt do but the temptation is just too much sometimes to get lost in the music. Even at times when headphones aren't needed, like when you're just sitting at home, nothing compares to that feeling of getting lost in the music and being completely cut off from all other sound. But yes, you're right. If we do this too much then we won't get the choice later in life, as to whether or not you hear other sounds. One of the many things we don't appreciate until we loose it!

To avoid that (as much) just try not to blast it in your ears. Being so close to the source of the sound is the main reason it's such a problem, so the ears are extra sensitive to it. And hey, if you're alone, noise isn't so much of a problem, right? Just keep the volume down you should be fine.