Honestly the more I think about it the more I seem to realize the secret ingredient (not the main one, but an important one) in Madonna's longevity is that she has never been fat. Unlike Paula, Gaga, Xtina, even Britney (she's never been truly fat but people said she was out of shape VMA 2007 and she got a lot of backlash), she's always been thin and in top shape. There's been comments about practically everything, but never about her weight.
She's been called chubby a lot when she first started.
but still. 
