Not defending the lard assess here but the scientific train of thought will most likely be that a certain minimal weight is required to be viable as a human. I guess it works better in German: ein BMI unter xx ist mit dem Leben unvereinbar.   Higher BMIs lead to death, but not everyone above a certain threshold is dead by default. Otherwise all the disgusting lardasses would drop dead the second they hit BMI 30+. What a nice thought though.