Originally Posted by Stefan Blom

There are several ways that you can reset formatting. You can get rid of direct paragraph formatting (that is, paragraph formatting not in style) by selecting all the text and pressing Ctrl+Q. Similarly, you can get rid of direct font formatting in the selection by pressing Ctrl+SpaceBar.

Alternatively, you can use the Find and Replace dialog (Ctrl+H) to search for a paragraph style and replace it with itself; this will reapply the style, which also clears direct formatting from the paragraphs using that style.