6 Common Causes of Underage Drinking

Underage drinking affects families and schools across the Treasure Valley and throughout Idaho. Adolescents facing stress or mental health challenges sometimes turn to drinking alcohol to cope, which can put their health and safety at risk. Understanding why teens drink, how alcohol affects a developing brain, and what steps parents can take can make a real difference.

To learn more about the causes of underage drinking, contact Zelus Recovery at 208.518.0797. We provide alcohol abuse treatment in Boise, Idaho that helps young people identify triggers and build coping skills that support better decision making.

What clinicians at Zelus Recovery are seeing

Our team works daily with teens, high school students, and young adults from Boise, Meridian, and surrounding communities. Many teens drink in social settings with little adult supervision, often at a friend’s home or at parties. Others start drinking alcohol to reduce anxiety or to feel less upset after a breakup or family conflict. We also see underage drinkers who report pressure from an older sibling or peer group, as well as those who start drinking simply because alcohol is easy to access in their environment.

When families learn the early warning signs, they can intervene sooner. Later in life, early alcohol use is linked with a higher risk of developing alcohol use disorder, so early support matters.

Idaho and national statistics at a glance

• For Idahoans ages 12–17, past‑month alcohol use is 7.2%, slightly higher than the national rate of 6.9%. Both Idaho and national rates have fallen by about 10% over the last two decades.
• NSDUH national data show that among people ages 12–20, millions report drinking and binge drinking in the past month. In 2024 estimates, 13.3% reported past‑month drinking and 7.6% reported past‑month binge drinking.
• Among adolescents ages 12–17, recent federal summaries note that girls report slightly higher past‑month alcohol use and binge drinking than boys.

Six causes of underage drinking

There is no single root cause of underage alcohol use. Most teens drink for a mix of reasons, often related to their social world, stress levels, and access to alcohol. The most common causes of underage drinking include:

Peer pressure and social acceptance

Teens drink to fit in, to feel confident in a new friend group, or to match what they see older teens doing. Clear rules, honest conversations, and practicing how to say no help teens drink less or delay when they start drinking. Many teens drink less when they have structured activities and positive adult supervision.

Stress, trauma, and mental health

Traumatic life events, family stress, grief, and untreated mental health conditions can raise the risk of alcohol use. Teens may drink to mute anxiety or depression. Integrating mental health care with substance use treatment reduces risk and supports better outcomes.

Low self‑esteem and identity development

A young person who feels insecure may use alcohol to appear relaxed or social. Building strengths, healthy peer connections, and better decision making skills reduces the appeal of drinking.

Boredom and free time

Without after‑school options, some teens drink alcohol because they feel bored. Sports, clubs, jobs, volunteering, and hobbies improve structure and reduce exposure to risky environments.

Curiosity and access

Most kids first try alcohol out of curiosity. Research shows many teens who drink get alcohol for free, often at home or from friends. Safe storage, monitoring, and consistent limits can lower access.

Family modeling and community norms

Teens drink more when adults around them drink heavily or binge drink. The Centers for Disease Control and Prevention overview notes that adolescent drinking is more likely when parents binge drink. Parents and caregivers can set a good example by modeling healthy choices, talking openly, and keeping alcoholic beverages secured.

If you think you or a loved may have an alcohol problem, Zelus Recovery is here to help. Don’t hesitate to contact us and find out your options.

How alcohol affects the developing brain

Alcohol affects brain development differently in people younger than 21 because the prefrontal cortex matures into the mid‑20s. This portion of the brain is involved in planning, memory, and impulse control. Exposure to alcohol during the teenage years can interfere with learning and impulse control, and it can increase the likelihood of other substance use.

Binge drinking and teenagers

Binge drinking is a pattern of drinking alcohol that brings blood alcohol concentration to 0.08% or higher. For a typical adult, that means five or more drinks for males or four or more drinks for females in about two hours. This definition helps families identify when drinking is dangerous.

Youth often drink less often than adults, but when they do drink, they drink more, which increases risk.

When alcohol becomes a problem, your teen may not be able to stop on their own safely. Learn about our Boise alcohol detox program if your teen is at risk.

Health and safety risks for young people

Underage drinking can lead to serious consequences, including:

• Alcohol poisoning, which can lower body temperature, slow breathing, and be life threatening. Review signs and call 911 if concerned.
• Injuries, motor vehicle crashes, and other emergency visits are more common when teens drink.
• Increased risk of violent behavior, physical and sexual assault, and unsafe sexual situations.
• Developing alcohol use disorder later in life, especially when teens start drinking early or engage in frequent binge drinking.
• Worsening of mental health conditions and interaction with other substances or medications.

Signs of underage drinking to watch for

Every teen is different, but common warning signs of underage drinking can include:

• Sudden changes in friends or a new social crowd, including older peers or an older sibling’s friends
• Slipping grades or missed practices
• Secretiveness, sneaking out, or unexplained money needs
• Smelling alcohol on breath or clothing, finding empty containers, or changes in the drinking environment at home
• Mood changes, irritability, or feeling upset after parties
• Coming home with injuries, or after risky behaviors like riding with a driver who has been drinking

What parents and caregivers can do

• Set clear rules and consequences about underage alcohol use, and revisit them each school year.
• Keep alcohol secured, monitor quantities, and ask about adult supervision before parties.
• Be a good example by avoiding excessive alcohol or binge drinking around teens.
• Practice refusal skills with your teen, so they can handle peer pressure.
• Agree on a safety plan, such as a no‑questions‑asked ride if they feel unsafe.
• Talk about how alcohol affects brain development and why waiting until the legal drinking age protects health.

If you are concerned now, call Zelus Recovery at 208.518.0797, or learn about alcohol use disorder and related services.

How Zelus Recovery helps teens and young adults

At Zelus Recovery, we tailor care for adolescents and young adults. Our clinicians use evidence-based therapies, including cognitive behavioral therapy and dialectical behavior therapy, to help teens understand triggers, manage stress, and reduce risky behaviors. Treatment can help a young person:

• Understand the risks of drinking alcohol and other substances
• Identify personal triggers and build healthier coping skills
• Improve communication with family and peers
• Strengthen decision making and reduce impulsive choices
• Address co‑occurring mental disorders, such as anxiety or depression
• Plan for school success and safe social activities

If your family needs support, explore our page on alcohol dependence to learn more about care pathways. You can also reach out to Zelus Recovery with questions.

Frequently asked questions

What is the most common reason teens drink alcohol?

The top reasons we hear are peer pressure, curiosity, and coping with stress. Many teens drink in social settings to fit in, especially when alcohol is easy to access from friends’ parents or at home.

Is it normal for a 15 year old to drink?

Many high school students report some alcohol use, but drinking under age 21 is illegal and unsafe. Waiting until the legal drinking age lowers risks and supports healthy brain development.

What is one thing that drinking can cause in teens?

Even a single episode of binge drinking can lead to alcohol poisoning, injury, or riding with an impaired driver. Repeated drinking can raise the risk of alcohol use disorder.

What is the 1‑2‑3 rule of drinking?

There is no official 1‑2‑3 rule endorsed by national institute guidance. Some adults talk about pacing drinks, but for people younger than 21, no amount of alcohol is safe or legal. Focus on refusal skills and safe plans instead.

What are five warning signs of underage drinking?

Look for changes in friends, slipping grades, secrecy, smell of alcohol or hidden containers, and mood swings after parties.

Ready to talk about next steps?

Underage drinking can create serious problems, but help works best when it starts early. Contact Zelus Recovery at 208.518.0797, or learn more about our Boise alcohol treatment programs for teens and young adults.