Is the "after 7 years skin cells that abuser won't have touched" thing actually true?

I've held onto that for the flashback moments of reminding myself how soon it will be that they never touched a cell on my body since I heard that once, and as I am processing that if it is true by the time I celebrate 3 years sober my abusive first boyfriend will have not touched a cell on my body. I just wanted to see before I get happy over that fact