Mass balance analysis of combustion not likely met.
Metabolic flammables like acetone are improbable, because : 1) The levels/volumes necessary for ignition and continued combustion would have reached lethal levels long before a flammability threshold was likely reached around their bodies. You would also suspect that diabetics would be more prone to combustion if that were the case and I have never seen a correlation. 2) No matter how you slice human spontaneous combustion theory - the mass balance equation for total combustion of tissues has to be met - meaning an adequate fuel source for the number of BTU's necessary for complete combustion and no one has been able to provide such an internal fuel source with that kind of BTU capability. Thus, the credibility gap.
