A recent study led by Brazilian researchers has found that parenting styles play a significant role in shaping adolescent alcohol and drug use. The research analyzed data from 4,280 adolescents and their guardians to determine how parental attitudes influence substance use among young people.
The findings indicate that parents' behavior regarding alcohol and drug consumption is one of the main factors affecting whether their children will also engage in these activities. However, the way parents educate and interact with their children can reduce this risk, even if the adults themselves use substances such as cigarettes, vapes (which are banned in Brazil), or marijuana.
The study identified that an "authoritative" parenting style—characterized by bonding, presence, dialogue, and clear rules—offers the greatest protective effect against substance use among adolescents. Other styles examined included authoritarian (which reduced drug but not alcohol use), permissive, and neglectful; only authoritative and to a lesser extent authoritarian styles showed protective effects.
Parental alcohol consumption was linked to a 24% chance of their children drinking alcohol and a 6% chance of using two or more drugs. When parents used multiple substances, these risks increased to 17% for single-substance use and 28% for multi-drug use among adolescents.
The results were published on the Addictive Behaviors website and detailed in the March issue of the journal.
"With this study, we reinforce the fact that parents' patterns of alcohol and other drug use influence their children's. However, if they set rules and limits at home and show affection, these protective factors greatly minimize the risk they themselves pose when they consume these substances. In addition, the greatest predictor of abstinence among young people is non-use by their guardians. When they're abstinent, 89% of adolescents also don't use alcohol or other legal or illegal drugs. This was the strongest association we found," said Zila Sanchez, professor at São Paulo School of Medicine at Federal University of São Paulo (UNIFESP) and lead author.
Sanchez coordinates UNIFESP's Research Center for the Prevention of Alcohol and Other Drug Use (PREVINA) and has previously studied links between parenting styles and youth substance abuse.
This research forms part of a larger project funded by FAPESP aimed at reducing adolescent alcohol consumption through community-based interventions. It took place in four small municipalities in São Paulo state: Cordeirópolis, Iracemápolis, Salesópolis, and Biritiba-Mirim—areas chosen for their diverse populations ranging from 18,000 to 25,000 residents.
"The article is based on data from what we call a needs assessment... We use extremely consolidated instruments to measure styles, but we innovate by working with the data alongside the consumption profiles of parents and children," Sanchez told Agência FAPESP.
Data were collected from all school-enrolled adolescents in those towns between 2023-2024; participants had an average age of about 14.7 years with gender parity. Among adolescents surveyed, nearly one-fifth reported consuming alcohol within the last month; episodic excessive drinking occurred among over one-tenth. For parents/guardians surveyed: more than half consumed alcohol recently; about one-fifth engaged in heavy drinking episodes.
Researchers used Latent Class Analysis (LCA) to categorize patterns within both generations’ substance usage profiles—and Latent Transition Analysis (LTA) to model associations between them.
Sanchez emphasized that even with positive parenting practices present at home—including emotional bonds—adolescent drinking still closely tracks parental drinking habits: "When consumption is frequent and treated as something trivial it translates into greater risk regardless of emotional bond."
Alcohol remains a major contributor globally to chronic diseases like cardiovascular illness or diabetes; it can also cause liver damage as well as mental health challenges such as anxiety or depression.
Delaying early exposure to addictive substances has been shown as an effective prevention strategy. Studies suggest that community-based programs—including family engagement—produce long-lasting benefits compared to isolated efforts alone.
Despite laws prohibiting sales to minors under age eighteen in Brazil [National Survey on Alcohol & Drugs], more than half try alcohol before adulthood while about one-fourth begin regular consumption during adolescence according to national surveys conducted by UNIFESP with partners including Brazil’s Ministry of Justice.
Recent survey results reveal just over one-quarter (27.6%) aged fourteen-to-seventeen have tried alcohol—a figure translating into roughly 3.2 million youths—with almost one-fifth reporting current-year usage (about 2.2 million). Regarding marijuana: approximately one million teenagers have ever used it; half did so within twelve months prior.
Among adults nationwide nearly nineteen percent report having tried at least one psychoactive substance apart from tobacco or alcoholic beverages.
