You Probably are a Cannibal.

Well, cannibalish.  Like the vegetarian of cannibals, as opposed to the vegan of cannibals you thought you were.  Unless you ate anyone I do not know about, and you and your Donner party are on your own.

Anyway, I was perusing the Vegetarian Journal's Guide to Food Ingredients, trying to update my knowledge of ingredients.  I was clicking around when I saw that a some amino acids such as L-cysteine, tryptophan, leucine, isoleucine, and valine may be derived from duck feathers, hog hair, or human hair.  Most of those amino acids primarily are used in nutritional supplements as far as comestibles, but the first, L-cysteine, is frequently found in bread products.  So next time you have a veggie burger and there is hair in your bun, it may be intentional.

Personally, I do not mind the human hair part, but 80% of it comes from duck feathers, although few manufacturers use vegan alternatives.  I imagine that the same issue is a concern in laboratories with amino acids there.  I sent a few emails out asking laboratory suppliers this.  I'll let you know what comes back.