Pennebaker: The simple answer is that is what we have found what works. But, since the original studies in the 1980s, many researchers (including me) have found that there is no one true way to write. Some studies have found that writing for as little as 2 minutes or as long as 30 minutes can be beneficial. Most studies have varied between 2 and 5 writing times with comparable effects. Sometimes people write multiple times on the same day. If you are thinking of trying out writing for yourself, experiment. See what works. If you are a researcher, experiment. See what works.