The Myth

• It's a popular myth that a deceased person's hair and fingernails grow after his or her death. However, this apparent growth is actually due to decomposition.
  
  

The Facts

• The British Medical Journal reports that this myth is based in fact, as "dehydration of the body after death and drying or desiccation may lead to retraction of the skin around the hair or nails." In other words, the dehydrating, receding skin may simply cause the illusion of longer hair or nails.
  
  True growth of hair and nails "requires a complex hormonal regulation not sustained after death," the journal adds.
  
  

The Decomposition Process

• According to BBC Health, how long the body experiences dehydration and decomposition depends upon many factors, such as how deeply the body is buried or the amount it's exposed to air or water. Coffins also help slow the decomposition process. Generally, the body is nearly fully decomposed within a year.
  
  

Interesting Fact

• A report in New Scientist magazine indicates that "funeral parlours put moisturiser on corpses to help reduce this effect."
  
  

Origin of the Myth

• According to New Scientist, medical students working with cadavers have commonly remarked upon this phenomenon. The magazine suggests that the myth might have made its way into popular culture through Erich Maria Remarque's classic 1929 novel "All Quiet on the Western Front," in which the character imagines a corpse with fingernails that continue to grow.