Natural explanations Almost all postulated cases of SHC involve people with low mobility due to advanced age or obesity, along with poor health. Victims show a high likelihood of having died in their sleep, or of having been unable to move once they had caught fire. Smoking is often seen as the source of fire. Natural causes such as heart attacks may lead to the victim dying, subsequently dropping the cigarette, which after a period of smouldering can ignite the victim's clothes. The "wick effect" hypothesis suggests that a small external flame source, such as a burning cigarette, chars the clothing of the victim at a location, splitting the skin and releasing subcutaneous fat, which is in turn absorbed into the burned clothing, acting as a wick. This combustion can continue for as long as the fuel is available. This hypothesis has been successfully tested with pig tissue and is consistent with evidence recovered from cases of human combustion. The human body typically has enough stored energy in fat and other chemical stores to fully combust the body; even lean people have several pounds of fat in their tissues. This fat, once heated by the burning clothing, wicks into the clothing much as candle wax is drawn into a lit candle wick, providing the fuel needed to keep the wick burning. The protein in the body also burns, but provides less energy than fat, with the water in the body being the main impediment to combustion. However, slow combustion, lasting hours, gives the water time to evaporate slowly. In an enclosed area, such as a house, this moisture will recondense nearby, possibly on windows. Feet don't typically burn because they often have the least fat; hands also have little fat, but may burn if resting on the abdomen, which provides all of the necessary fat for combustion. Scalding can cause burn-like injuries, sometimes leading to death, without setting fire to clothing. Although not applicable in cases where the body is charred and burnt, this has been suggested as a cause in at least one claimed SHC-like event. Brian J. Ford has suggested that ketosis, possibly caused by alcoholism or low-carb dieting, produces acetone, which is highly flammable and could therefore lead to apparently spontaneous combustion. SHC can be confused with self-immolation as a form of suicide. In the West, self-immolation accounts for 1% of suicides, while Radford claims in developing countries the figure can be as high as 40%. Sometimes there are reasonable explanations for the deaths, but proponents ignore official autopsies and contradictory evidence in favor of anecdotal accounts and personal testimonies. Inhaling/digesting phosphorus in different forms may lead to the formation of phosphine, which can autoignite.
natural explanations almost all postulated cases of shc involve people with low mobility due to advanced age or obesity along with poor health victims show a high likelihood of having died in their sleep or of having been unable to move once they had caught fire smoking is often seen as the source of fire natural causes such as heart attacks may lead to the victim dying subsequently dropping the cigarette which after a period of smouldering can ignite the victim's clothes the "wick effect" hypothesis suggests that a small external flame source such as a burning cigarette chars the clothing of the victim at a location splitting the skin and releasing subcutaneous fat which is in turn absorbed into the burned clothing acting as a wick this combustion can continue for as long as the fuel is available this hypothesis has been successfully tested with pig tissue and is consistent with evidence recovered from cases of human combustion the human body typically has enough stored energy in fat and other chemical stores to fully combust the body; even lean people have several pounds of fat in their tissues this fat once heated by the burning clothing wicks into the clothing much as candle wax is drawn into a lit candle wick providing the fuel needed to keep the wick burning the protein in the body also burns but provides less energy than fat with the water in the body being the main impediment to combustion however slow combustion lasting hours gives the water time to evaporate slowly in an enclosed area such as a house this moisture will recondense nearby possibly on windows feet don't typically burn because they often have the least fat; hands also have little fat but may burn if resting on the abdomen which provides all of the necessary fat for combustion scalding can cause burn-like injuries sometimes leading to death without setting fire to clothing although not applicable in cases where the body is charred and burnt this has been suggested as a cause in at least one claimed shc-like event brian j ford has suggested that ketosis possibly caused by alcoholism or low-carb dieting produces acetone which is highly flammable and could therefore lead to apparently spontaneous combustion shc can be confused with self-immolation as a form of suicide in the west self-immolation accounts for 1% of suicides while radford claims in developing countries the figure can be as high as 40% sometimes there are reasonable explanations for the deaths but proponents ignore official autopsies and contradictory evidence in favor of anecdotal accounts and personal testimonies inhaling/digesting phosphorus in different forms may lead to the formation of phosphine which can autoignite