I kind of brace myself, and wait to see what mindset the person has.
Are they T1, T2, T3? Low carb, high carb, Healthy Plate, I-eat-wot-I-like-and-don't-you-dare-infringe-my-civil-liberties-by-implying-my-eating-ain't-perfick.
Are they young, old, fit, unfit, active, sedentary? Any other health issues? co-morbidities? Religious or ethical beliefs affecting diet choice and treatment options?
What medications are they on?
What previous experiences have they had with doctors, nurses, consultants, emergency services, family history...
And are they in the slightest bit interested in talking about D?
Most people aren't. Or they KNOW EVERYTHING about D already and want to lecture me. Interminably.
Gotta respect all that. Except for the lecturing. Can't be bothered with that.
Basically, I avoid the subject completely, with anyone who hasn't chosen to be on this or other forums, unless they already know my interest in the subject. I certainly don't discuss it with health care professionals. I haven't met many who are interested in discussion. We have had a few exchanges of view, though. And several HCPs have gone out of their way to avoid discussion, and lecture instead.