Gotta love docs! (not all of them!)
My suggestion would be to measure yourself right now... arms, neck, bust, waist, calf, hips, etc. Then keep doing what you're doing. Right before you go back in, measure yourself again and take that information with you.
That should give you better ammo. He will most certainly still look perplexed but it may shut him up.
Agreed on the VAP... it is a much better measure.
Interesting fact... thyroid issues can cause your cholesterol to go up. My TSH went up for a while and my last cholesterol test was higher (231). In four months, the TSH came back down and my cholesterol was 181. Go figure. Ate the same way, it was just a symptom of another issue.