Newsprint is high in acid. You've probably noticed how quickly newspapers yellow, especially in the light. They also become brittle with age. It's remarkable that even this worst of papers lasts a hundred years or more if it's handled carefully. If you want your documents to last, print them on archival quality paper.
Papers are either acidic or alkaline.
This is measured by the pH scale. Archival papers should be slightly alkaline. Eight or higher would be better. The paper also should contain calcium carbonate. Any paper bought from a conservation supplier should be reliable.