Alcohol’s Low Dose Effect & Tolerance

One of the biggest hurdles to alcohol prevention efforts is the affinity drinkers have towards the “buzz” consuming alcohol gives them. Teaching drinkers the real physical effects alcohol causes vs. the expectancy effects our brains associate with drinking is an effective way to reduce binge drinking.

This interview was filmed after the television premier of the documentary Smashed. In it I explain why drinkers are conditioned to feel all kinds of pleasurable experiences from drinking that are not caused by the chemical alcohol. I’m elaborating on the central thesis of  the Alcohol Literacy Challenge Curricula: that if drinkers know most of the pleasurable effects of alcohol they’re seeking are created by their minds, not by what they’re drinking, they tend to drink less.
I discuss the Low Dose Effect beginning at 2:53 in the video.
Drinkers get a “buzz” at extremely low doses of alcohol—one or two standard drinks for most people. After this low dose, the buzz diminishes. When a person who has passed this threshold continues to drink, the alcohol consumed will diminish the buzzed feeling. Eventually, a person reaches a point where the alcohol actually makes them feel worse and they’ll experience a kind of anti-buzz. Depending on how much a person weighs, this point where a person feels worse than when she or he started drinking is reached at about 2-4 standard drinks.

This chart can help explain the low dose effect. A person’s buzz increases until he or she hits about .05 BAC. People who drink past .05 BAC are simply wasting good alcohol, as their buzz decreases. At about .1 BAC a drinker actually begins feels worse. A person can gage the BAC achieved from drinking by knowing their weight. At 150 lbs, a person’s buzz will peak at 1 drink and be gone after 2. There will be slight variations of this formula depending on a person’s sex or race, but as a rule of thumb, knowing one’s weight is the simplest way to gage the anticipated BAC from drinking.
The next chart explains how much of various kinds of alcohol is one standard drink. It measures the percentage of the drink’s content that is actually alcohol.

Of course, tolerance to alcohol throws a wrench into a drinker’s plan to enjoy a buzz that could otherwise be obtained from a low dose of alcohol. I address tolerance at the 4:05 mark in the above video.
Tolerance can be described as needing more alcohol in order to achieve the same effect one experienced at a lower level of use. For example, a person who has developed tolerance may notice that they now need 4 drinks to feel relaxed or “buzzed” when they used to experience those effects after 2 drinks. Although tolerance may result in shifts of effects experienced, BAC remains relatively unchanged with tolerance. In other words, the amount of alcohol consumed will result in the same level of intoxication, but the person may need to achieve higher BAC’s to experience similar mental expectancy effects.
The consequence of gaining tolerance most likely leads to an increase in the amount of alcohol used, increased BAC levels, and also increased financial impact (as a person is now paying for 4 drinks when he or she used to only buy 2). Drinkers with tolerance are also likely to experience an increased risk for negative consequences. Persons with a higher tolerance are achieving higher levels of intoxication and also experiencing the degree of impairment associated with that BAC. Therefore, judgments about how impaired she or he actually are will become increasingly less accurate and may lead to poor decision-making. For instance, a person may be more likely to make the decision to have another drink or decide that they are able to drive.
Fortunately, tolerance is something that once achieved, can be decreased and eliminated. Simply taking a break from drinking or decreasing the quantity or frequency of alcohol use can reduce tolerance. For all but the heaviest drinkers, going two weeks without alcohol will lead to significantly decreased tolerance. Of course, if a person can’t go two weeks without drinking, she or he has much bigger problems than are being discussed here. Such a person is likely dealing with alcohol dependence issues or full blown alcoholism.
At the college level, teaching about alcohol’s low dose effect and tolerance are harm reduction strategies prevention specialists may wish to consider. The College Alcohol Literacy Challenge Curriculum is designed to do this (the Middle & High School ALC Curricula teaches prevention from the Zero Tolerance perspective of underage alcohol use). To learn more, please read this explanation of how the Alcohol Literacy Challenge addresses problem drinking on college campuses. You can also view a slide show explaining how alcohol expectancy theory can be applied to prevention. You can also purchase the Alcohol Literacy Challenge.
Blessings,
Peter D.