A disease is something you either have, or you don't. It's a little like being pregnant. You either are, or you are not. You can't be a little bit pregnant. There is no middle ground. When we view addiction as a disease, there is one dividing line. On one side of this line is the disease of addiction or alcoholism. On the other side of the line might be occasional and infrequent alcohol problems, or just abstainers or social drinkers, but no alcoholics. There might also be individuals who are progressing toward "crossing the line." The disease model of addiction suggests that someone might exhibit a loss of control over addiction because of an underlying disease. You would need to treat the disease according to methods that have been developed for arresting this disease. At best, the disease can be placed into remission by complete abstinence. Moderation is no longer an option once the disease of addiction has developed.
We maintain that all addictions represent a complex interaction between biological, psychological, social, and spiritual forces. Psychologists often call this the Bio-Psycho-Social-Spiritual (BPSS) model of addiction. From this BPSS perspective, addiction is a complex and dynamic process. It is not as simple as the disease model where you either have addiction (disease) or you don't. From the BPSS model, addiction problems may range in severity from none, to severe and they may change across time. For instance, using alcohol as an example, you could have abstainers. Next would be low risk drinkers (sometimes called "social drinkers" or "moderate drinkers"). Then after that would medium risk drinkers. Finally, there would be the high-risk drinkers. Some people also call this the use-abuse-addiction continuum. Because of broad range of problem severity (from none to severe), the BPSS model also implies there would be different recovery approaches. The approach would vary upon the severity of a person's problem. For some people moderation might be the best approach, for others complete abstinence may be best. While the BPSS model is more complicated than a disease concept of addiction, it more accurately captures human diversity.