It can't. So it must be something else.
It's easy to see if the docs contain images. Docs with images are much larger (in bytes) then docs with links to images. Only you can see how big your file is. If it contains all images, it must be bigger than all those image taken together. If it's just text and links it will be much smaller than that.
Anyway, IF the documents are corrupted by some other reason, replace them by your last backup of a good version. That's why you backup.