lose sleep over, to

lose sleep over someone or something

 and lose sleep about someone or somethingFig. to worry about someone or something a lot, sometimes when one should be sleeping. (Often used with any and the negative.) Yes, Kelly is in a little bit of trouble, but I'm not going to lose any sleep over her. Don't lose any sleep over the matter. I refuse to lose sleep about it.See also: lose, over, sleep

lose sleep over

Worry about, as in It's too bad the experiment failed, but I'm not going to lose sleep over it. This expression, often put negatively, alludes to actual insomnia caused by anxiety. [First half of 1900s] See also: lose, over, sleep

lose sleep over, to

To worry about. This expression, often used negatively—that is, something not to lose sleep over, dates from the mid-twentieth century. The novelist Norman Mailer used it in Advertisements for Myself (1959), “It’s not the sort of thing I lose sleep over.”See also: lose, sleep