The Bizarre Reason Your Hair And Nails Look Like They Keep Growing After Death

If you've heard that your hair and nails continue to grow after death, you may be wondering how on earth that is possible. Well, the simple answer is — they don't. It is in fact, an optical illusion based on everything else that is happening in the body (or not) once the last breath has been taken. 

The claim has long been perpetuated in fiction, and the hair and nails on a corpse can indeed appear to have grown post-mortem. But given that all other life processes have stopped, the idea that these would continue to grow does seem unlikely. 

Fingernails are produced from living tissue and only grow around 4 millimeters per month, and only while you are alive. Likewise, hair is only grown from living cells at a rate of around 13 millimeters per month. It's just not possible for either to suddenly grow a noticeable amount when the rest of the body has ceased to function.

In a living, breathing human, the hair follicles and nail matrices create new cells and push the existing material away, making both longer in the process. This can only happen because the body is taking in oxygen and glucose to create the energy needed for this process. Unsurprisingly, after death, respiration no longer takes place, making it impossible for any sort of growth to happen in the now dead body.

What does happen, though, is dehydration in the skin, which can make it appear tighter. If this happens around the fingers or the skull, it can make the hair or nails seem longer in relation to the skin. More of the nail or hair is exposed than previously, giving the illusion of them having grown after death, even though nothing has actually changed. The same thing can happen on the faces of men, as the skin on the chin dries out and tightens. This explains reports of men having more stubble on their face after death than they did in their final moments. 

 So while those who have read All Quiet on the Western Front may forever have images of corpses with long nails growing into corkscrews, you can be reassured that optical illusions are to blame for this phenomenon. When your time comes, your hair and nails will not suddenly take on a life of their own, despite what your favorite horror movie might suggest.