Digital Light & Color

Probably the only details that would change would be very hard to see. JPEG is designed to discard information from images to which human viewers are insensitive, so even if there are small differences from repeated JPEG saves that does not mean that you would be likely to notice them. That being said, it is better practice to store images you are likely to rework as TIFF, especially for 16-bit images which cannot be saved as JPEG anyway, and reserve JPEG for exporting for posting on the web or for email where size is more important than quality.