A good and comfortable pillow is the key to a good and restful sleep. In fact, it can often be the cause of not sleeping well at night.
In particular, if the pillow is not in good condition it can cause headaches, dizziness and cramps and various allergies have been observed due to its interior.
So when is the right time to change that? The average replacement of a pillow is about 3 years but there is a way to know if it needs immediate change.
All you have to do is fold the pillow in half, as if it were a sheet of paper. If it remains for a while in the place where you placed it, it means that it is completely useless and you must change it immediately.