Most recovering alcoholics would refer to alcoholism/addiction as a spiritual malady. If you limit discussion of it to a simple "nature vs. nurture" you're ultimately going to have two sides that merely condone the behavior of the addict or alcoholic. The "nature" side will excuse the practitioner as having been, "born that way." The "nurture" side would argue that a learned behavior can be unlearned. It's been my experience with more than a few years of sobriety under my belt, that until and unless one is willing to recognize the spiritual component and dimension of the dysfunction, one will never start down the path of solid recovery.
"I can catch cold, I can't catch heroin."
One of the early founders of AA was a medical doctor who likened the physiological effects of alcoholism to an allergy. It's not something you "catch", but it's something different people react to differently. Subsequent studies of alcohlics have established that their bodies and brains respond differently to alcohol than do those who are not alcoholics, so there is a physiological difference. The question, to the best of my knowledge, remains unsettled as to whether those changes are inborn or if they develop over time with the consumption of alcohol. Certainly there are some who appear to be predisposed to alcoholism.
First of all, I do agree that some are more prone to addictions than others. I have a friend who can get a strong habit out of just about anything. But I strongly object to calling it a disease.
For instance there is billboards promoting stomach surgery saying “Overeating is a disease, not a choice!” The implication is that it is not your fault for you addiction.
A habit can be very strong, but that still has an element of will in it.
Bingo!