I have tried various approached over the years, but most recently I have avoided the term Low Carb and High Fat, or any other trigger words that may set off an ignorant knee jerk reaction.
Last time I used the words 'I control my carbs, which is what brought my blood glucose down to normal levels'.
And since they had just seen my perfectly normal HbA1c they just let it go, and moved on to the next subject.
Either that or they didn't 'get' what I was talking about.
Of course, if a medical professional wanted to discuss things in more depth, I would happily do so. Probably in enough detail that they ran screaming from the room.
But until that happy day arrives, I can say 'I control my carbs' and they can hear 'she's eating carbs which is a good thing, cos of 50 reasons I repeat by rote which aren't actually valid', while what I actually MEAN is 'I control my carbs well enough that I have virtually eliminated them, and feel soooooo much better for it!'