From 2000 to 2019, the percentage of Quebec high school students who had drunk alcohol in the previous year dropped from 71.3% to 53.2%—a significant decline! During the same period, among all teens, the percentage of those who had consumed at least five alcoholic beverages on a single occasion fell from 45.6% to 32.2%.1
However, considering only at those teens who drink alcohol, the percentage of those who drink excessively has stayed about the same, dropping just three points from 64% to 61%. In other words, young people who drink alcohol are still at the same risk of abusing it. Also, the drinking habits of teens differ from those of adults in many ways. Young people tend to drink less frequently, but they generally drink excessively each time.
However, considering only at those teens who drink alcohol, the percentage of those who drink excessively has stayed about the same, dropping just three points from 64% to 61%. In other words, young people who drink alcohol are still at the same risk of abusing it. Also, the drinking habits of teens differ from those of adults in many ways. Young people tend to drink less frequently, but they generally drink excessively each time.2
Circumstances in which teens drink
In a society in which more than half the population, including teens, drinks alcohol, it is to be expected that teens will be exposed to an increasing number of opportunities to drink as they progress through high school. But studies1 show that some circumstances are less harmful than others.
When young people are in the habit of drinking alcohol with their friends, they are about 2.5 times more at risk of drinking excessively or getting drunk on any given occasion. Conversely, the risk is cut almost by three when teens are in the habit of drinking alcohol with their parents.
When it comes to some of the consequences of drinking, such as missing school or forgetting what happened the night before, the same holds true: the risk is a little more than doubled when teens drink with their friends, but cut by a little more than half when they drink with their parents.
Note that we are speaking specifically about the circumstances in which the drinking occurs, i.e. with whom the teens are drinking, not who is providing the alcohol. While the risk of getting drunk is lower when teenagers organize a party with alcohol, under the supervision of their parents, it is a very different story when other adults provide the alcohol but leave the kids unsupervised; the risk of excessive drinking is then higher.
Impact on the teenage brain
The human brain continues to develop until about the age of 25. The brain matures region by region, with the frontal lobe developing last. As a whole, the frontal lobe is responsible for what we call the executive functions, such as planning, impulse control and focus.
Because the frontal regions of the brain are still fragile in teens, a more rapid decline in grey matter is observed in young people who drink excessively,3 unrelated to the concomitant consumption of cannabis. These developmental disturbances are even more pronounced among the youngest teens, in two specific regions: some of the frontal regions, which are primarily responsible for executive function, and some of the temporal regions, which are responsible for proper memory function.4
The development of white matter, which contains the complex network that ensures good communication between the different regions of the brain, is also affected by excessive drinking during adolescence, and the damage is proportional to drinking frequency.5. Thus, certain complex tasks that require good coordination between various regions of the brain could be affected significantly.
The negative impact on brain function in these regions may not be felt immediately following a few episodes of excessive drinking. There is some indication that excessive drinking during adolescence needs to have occurred for at least two years in order for a notable impact on performance to be detectable.6
Ironically, the very same functions that could help teens limit their drinking are not yet fully developed in the teenage brain. And unfortunately, these same regions of the brain are particularly affected by excessive alcohol consumption, thus exacerbating problems with various executive functions that are essential in transitioning to adulthood.
Your children and drinking: Four things to remember
- Alcohol hinders the development of a young person’s brain. Therefore, children should wait as long as possible before having their first drink.
- When it comes to drinking, parents are the primary role models for their children and should be sure to drink moderately and responsibly in front of their children from an early age.
- Parents should explain to their children why they are setting limits and imposing conditions on drinking.
- When children participate in setting the drinking rules and conditions, they are more likely to stick to them.
 Institut de la statistique du Québec (2013, 2019), Enquête québécoise sur le tabac, l’alcool, la drogue et le jeu chez les élèves du secondaire
 Song, E. Y., Smiler, A. P., Wagoner, K. G., & Wolfson, M. (2012). Everyone says it’s ok: adolescents’ perceptions of peer, parent, and community alcohol norms, alcohol consumption, and alcohol-related consequences. Substance use & misuse, 47(1), 86-98.
 Squeglia, L. M., Tapert, S. F., Sullivan, E. V., Jacobus, J., Meloy, M. J., Rohlfing, T., & Pfefferbaum, A. (2015). Brain development in heavy-drinking adolescents. American journal of psychiatry, 172(6), 531-542
 Pfefferbaum, A., Kwon, D., Brumback, T., Thompson, W. K., Cummins, K., Tapert, S. F., … & Sullivan, E. V. (2018). Altered brain developmental trajectories in adolescents after initiating drinking. American journal of psychiatry, 175(4), 370-380.
 Infante, M. A., Zhang, Y., Brumback, T., Brown, S. A., Colrain, I. M., Baker, F. C., … & Thompson, W. K. (2021). Adolescent Binge Drinking is Associated with Accelerated Decline of Gray Matter Volume. bioRxiv.
 Zhao, Q., Sullivan, E. V., Honnorat, N., Adeli, E., Podhajsky, S., De Bellis, M. D., … & Pohl, K. M. (2021). Association of heavy drinking with deviant fiber tract development in frontal brain systems in adolescents. JAMA psychiatry, 78(4), 407-415.
 Tapert, S. F., Brown, G. G., Kindermann, S. S., Cheung, E. H., Frank, L. R., & Brown, S. A. (2001). fMRI measurement of brain dysfunction in alcohol‐dependent young women. Alcoholism: Clinical and Experimental Research, 25(2), 236-245
 Tapert, S. F., Schweinsburg, A. D., Barlett, V. C., Brown, S. A., Frank, L. R., Brown, G. G., & Meloy, M. J. (2004). Blood oxygen level dependent response and spatial working memory in adolescents with alcohol use disorders. Alcoholism: Clinical and Experimental Research, 28(10), 1577-1586.