Dry Skin after Surgery. I am so curious what causes it

I had a breast augmentation last year and a tummy tuck a couple weeks ago. My recovery for both times have been fantastic, There is only one minor issue that I seem to be unable to find the answer anywhere: For each of the above-mentioned surgeries, a week or 2 after, my skin starts to slough off. It isn't exactly dry, but just flakes off allover the body. I am so curious what causes it and greatly appreciate the experts' light shed upon the matter.