Is food with hair in it (or food which had hair in it) safe to eat?
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Hair is a protein mostly keratin


  Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails.


There's nothing special about it as a protein, so as long as it doesn't wrap around your tonsils and get stuck in your throat, or contain dyes, hairspray etc. it's safe to eat.
However, the long stringy nature of the stuff can cause problems if you eat too much of it.