The phrase “cold turkey” had the folk symbolism of stark circumstances without the trimmings before it first appeared in print as a reference to drug withdrawal in 1921.
An example, an unadorned sandwich made from the leftovers of a feast as a symbol of having seen better times.
The expression gained credence from the withdrawing addicts’ desperate appearance, cold, pale, pimply skin, making them resemble a cold, uncooked turkey.