@wend50 - When I was diagnosed, I decided to tell only those who really, really needed to know, so that was my partner, my close family and any health care professionals to whom it mattered. Everyone else? Nope.
Obviously, like the rest of us, I had to tweak my diet a bit to get the numbers down, but when people asked why I wasn't eating or drinking x, y or z, I just said I'd had some blood tests done and they showed certain things I was eating and drinking weren't doing me any favours, so I'd given them up for now.
Almost 7 years on "for now" is still the case, but to be honest, after an initial raised eyebrow or two, nobody bothers any more. The odd acquaintance I haven't seen for a while might asking in passing if I'm still of biscuits (or whatever), and I just explain I got used to it and decided just not to bother with it/them any more.
Generally, in my opinion, most people are curious, as opposed to deeply interested. I just can't be bothered to feed their curiosity and get a hard time in return.
Of course, it isn't the right approach for everyone, but it seems to have worked OK for me.