Don't get fat, but by all means don't get too thin

For quite some time, I've had a BMI that's on the high side of normal. And I've always wanted to be thinner. I've done a good job of maintaining my weight thanks to healthy eating (with some indulgences along the way, to be sure) and very, very assiduous exercise every single day.
Even so, I've longed to weigh 5-10 pounds less than I do.
But over the winter when I was in the hospital twice for a heart issue, two different nurses told me that my weight was perfect.
And I know what they mean -- a thinner body also means a thinner face, and my already prominent wrinkles and sag would just look worse.
So I'm trying to be OK with the weight that I'm at.

She's elegant, but TOO thin