Isn't it easier to eat such that there's no excess in the first place?
I totally understand the appeal, hell I'd do it myself if you could give me a guarantee, my problem with it is there is no guarantee and it's 99.9% likely to not actually be safe.
Even better would be an implant that not only removes excess glucose (or other material) from your bloodstream, but also monitors your bloodstream for nutrients and tells you the levels of all of them, and lets you know when you're deficient in something. Then you can get a notification on your phone from your implants saying "Warning: your iron level is low. Please eat some beets soon."
Not all of us are wired the same. Some of us have neurological deficiencies or disabilities that make regulating food intake very difficult. So I would never presume easier.