what causes spontaneous combustion in humans

Spontaneous human combustion is a phenomenon where a human body is found with significant portions of the middle parts of the body reduced to ashes, with much less damage to the surrounding area. However, the scientific consensus is that incidents which might appear as spontaneous combustion did in fact have an external source of ignition, and that spontaneous human combustion without an external ignition source is extremely implausible. There are several proposed scientific explanations for how a body would spontaneously burst into flames, but none of them have held up to scrutiny. The most likely explanation for suspected cases of spontaneous human combustion is that there is an external source of ignition, such as a lit cigarette, lamp, or candle. Therefore, spontaneous human combustion in humans is not a real phenomenon, and there is no scientific evidence to support it.