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In the early 19th century, oysters were cheap and mainly eaten by the working class. Oysters' popularity put an ever-increasing demands on wild oyster stock. This scarcity increased prices, converting them from their original role as working class food to their current status as an expensive delicacy.

Nowadays most oysters are farmed. Their bivalve nature made eating them a little bit like Russian roulette! But nowadays the unpleasant side-effects are much more rare.