Don’t go into your doctors office looking for a fight!
So today - doctor’s visit. I was by no means overweight a year ago, so weight was not brought up - by the doctor. But, I happily told him I had lost 16 pounds in the last year. He asked “how?” I said “I drastically cut carbs and no sugar” (no lie there.) His response? “Good, carbs are everywhere, best to avoid them.” Win-win. No need to mention the “K” word if you and the doctor would not be comfortable (or in the doctor’s case, knowledgeable) about that.
I must admit my group of doctors have all been extremely supportive of keto. They have had nothing but good things to say 
I just had a good appointment with a new doctor and did exactly this. I told her how much I’ve lost this past year due to low carb, no sugar, gluten, watching calories and exercising and she was pleased. She said I “could stand to gain a few pounds even” which I have no problem hearing. She also talked about her own weight loss, quitting sugar and stopping her own diabetes.