Pillow not change every six months?

If you have not changed this information for years after your pillow every six months you will start to change your pillow.
          Sleep to Live Institute in Britain believed that his research using a cushion of more than six months, asthma, allergies and acne is more risk of problems like.
Why is it important to change the pillow?
          The researchers based their study is supposed to stay on the pillow dust, oil, dead cells of the body, allergies, acne, asthma and skin problems threaten.
           During research on 2,200 men and women and found that 82 percent of study participants were not aware when they should change the pillow.
And also damage
            Attached to the neck and spine problems that may occur.