Plenty of urban legends and misconceptions surround death. The recently-departed are said to be able to continue growing fingernails and hair. (That’s a myth.) Or the bodies may transmit pathogens, sickening coroners or other handlers. (Also not true, though hepatitis and tuberculosis can be rare exceptions.)
Some myths are actually rooted in reality. Corpses can move a little as their ligaments stiffen, for example. But can the skin of a decedent experience a tan? Or is that strictly for the living?
Surprisingly, it can. A paper published in The American Journal of Forensic Medicine and Pathology in 2023 (link here but beware some potentially disturbing images of dead bodies) tackled this very issue. Dubbed “postmortem tanning,” the paper analyzed three instances of bodies that demonstrated sun damage via tan lines that matched their clothing.
In the first, a woman was found frozen. After thawing out in a laboratory setting, the body presented “brown pigment transformation” on exposed areas of the skin. The skin underneath her clothing, however, was unaffected.
Another body, this one male, was recovered following a motor vehicle accident. The tanned skin was consistent with the awkward pattern of their clothing arrangement, as they were a pedestrian struck by a car. Skin exposed as a result of bunched-up clothing was darkened following sun exposure during the several hours the body was left before it was located and retrieved.
The third case, this one a male who had a self-inflicted fatal gunshot wound, also presented with tanned skin from an area of the body exposed due to rumpled clothing.
What makes these scenarios unique is that tanning is essentially the skin’s response to damaging ultraviolet (UV) rays, a metabolic process that would seem to be nonexistent in the dead. In two of the cases, the bodies were discovered in freezing temperatures, leading authors to theorize that the necessary metabolic pathways were preserved. But that fails to explain the third body, which was retrieved in a warm summer climate.
The paper does not indicate whether any of the three bodies were actually sunburned, only tan. Sunburn is defined as erythema (redness) and blistering in the hours or days following sun exposure. As these symptoms weren’t mentioned, it’s unclear whether a dead body can mount such a response.
It’s important to note that there are other causes of skin color changes in death. Mummification can prompt darkening of the skin when it becomes dehydrated and brittle, as in dry, hot climates. There’s also a phenomenon known as “bog body formation,” in which corpses left in acidic peat bogs prompt a chemical response in the skin that can lead to browning.
While the subject matter may appear morbid, postmortem tanning could be a key factor in forensic analysis. Posthumous sunning can help determine a time of death and potentially lead to answers in a criminal investigation. Of course, sun exposure can also be a cause of death, too, which is why you should always wear sunscreen.
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