Is it a compliment when others say you really know how to hold your liquor?
ADDICTION Overdrinking impairs thinking and behavior. In far too many cases, it quite literally becomes a "license to kill." Tolerance suggests a plateau at which prior intoxicating amounts cause no outwardly observable effects; increasing amounts of alcohol are required to trigger symptomatic intoxication. So is high tolerance a good thing?
First there is need to define what type of tolerance is being considered.
- Acute tolerance is when alcohol-induced impairment is greater when measured soon after beginning alcohol consumption than when measured later in the drinking session, even if the blood-alcohol concentration (BAC) is the same at both times.
- Functional tolerance involves the body's compensation for alcohol disruption, resulting in seemingly consistent behavior and bodily function.
- Environment-dependent tolerance manifests apparent tolerance to alcohol effects if always administered in the same environment or accompanied by identical cues.
- Environment-independent tolerance is evident when large amounts alcohol can be consumed without apparent effects independent of environmental influences.
- Learned tolerance is the development of tolerance behaviorally by practicing a task while under the influence of alcohol.
- Metabolic tolerance results from rapid elimination of alcohol from the body. Enzyme activation increases alcohol degradation and reduces the active alcohol absorption duration, thereby reducing the intoxicating effects.
Animal studies indicate that some aspects of tolerance are genetically determined. But there are social, emotional, and physical effects. Tolerance can predispose one to increased or binge drinking, at the risk for alcoholism, liver and brain damage.
There is currently no worldwide consensus on how many drinks constitute a "binge", but the term is often taken to mean consuming five or more standard drinks (male), or four or more drinks (female), in about one hour for a typical adult. This is called the "5/4 definition." However, these numbers vary significantly based on weight and numerous other variables. Other, less common definitions are based on blood alcohol concentration. For example, the NIAAA recently redefined the term "binge drinking" as anytime one reaches a peak BAC of 0.08% or higher as opposed to some (arguably) arbitrary number of drinks in an evening.