I think mass relates to volume, not area!?
So who would have thought that something that related weight to only the *square* of length would be a bad measure for individual analysis? 
https://www.bbc.co.uk/news/uk-politics-56669834
Even the people who invented and proposed it, actually.
Well doh!, clearly it should be the *cube*.
Oh, there is already such a measure, and it is used in pediatrics, apparently, because BMI doesn’t work.
https://en.wikipedia.org/wiki/Ponderal_index
And surprise, surprise, it’s “better” for different gender, age and shape.
