Why alcohol is so dangerous for the brain of young people

From the European myth of a "healthy drinking culture" to the surprising effects of regular family meals, science is overturning old beliefs about alcohol and youth.

I turned 18 the day before I left home for university, easily passing the UK age limit by buying alcohol in time to explore the student pubs. When I checked in with a doctor near my new home, he asked me how many alcohol tests I drank each week - the standard way to measure alcohol consumption here in the UK, with 1.5 units roughly equivalent to a small glass of wine. "About seven," I said, hastily putting down a few vodkas-and-oranges that I would enjoy all night with my friends from school. I thought this was low, but I've never been much of a lawbreaker.

"That will go up now you here," the doctor replied with a dry laugh. He was not wrong. Within weeks, I was happily drinking a bottle of wine before planning a shot at the student bar. I knew that drinking too much alcohol could cause lifelong harm, but I hadn't considered that my youth would be more dangerous, compared to someone in their 30s, 40s or 50s. Were the risks the same for all adults?

If I had heard what I know now about the unique ways alcohol can affect the adolescent brain, I might have been more careful. At 18, my brain was still developing, and wouldn't mature for at least seven years. This changes how we react to alcohol - and drinking during this critical period can have long-term consequences for our cognitive development.

Talking to researchers about the effects of alcohol on young people, I was surprised by many other findings besides these. Research from around the world is beginning to overturn many common assumptions about age and alcohol, such as the idea that continental Europeans have a healthier drinking culture than Britain or the United States, and that allowing young people to drink at home with meals teaches them alcohol responsibility. Whether or not this new science should change our current drinking laws is a complicated political issue, but a better understanding of the facts may at least allow future generations to make better choices about the ways they choose to party — and may help parents decide. how to handle alcohol in their home.

Small bodies, big minds

Let's be clear: alcohol is poison. Its risks include serious accidents, liver diseases, and many types of cancer. Even small amounts can cause cancer, leading the World Health Organization to declare that "when it comes to alcohol consumption, there is no safe amount that does not harm health".

Few activities are completely risk-free, though, and the risks tend to be weighed against the pleasures that alcohol can bring. So our health policies are guided by the principle of harm prevention and moderate drinking. In the United States this is defined as not drinking more than two drinks a day for men,

and no more than one drink a day for women - with many other countries offering similar guidance. Although beer and wine are usually seen as the safest drinks, as the US guidelines say, the type of drink is not the important factor - rather, it is the amount of alcohol consumed: "One 12-ounce beer contains about the same amount of alcohol. One glass of five ounces of wine or a 1.5 ounce shot of alcohol." Laws around the age of purchasing alcohol follow the same logic of damage prevention: laws protect children, while allowing young people to make their own choices. In most European countries, the minimum age is 18 - in the US it is 21.

However, there are many reasons why alcohol can be more dangerous for young people, even after passing the minimum drinking age. One is body size and shape: young people don't reach their adult height until 21, and even after they stop growing vertically, they may lack the bulk of a 30- or 40-year-old. "Drinking one glass of alcohol therefore causes higher blood alcohol levels in young people than in adults," says Ruud Roodbeen, a postdoctoral researcher at Maastricht University and author of Beyond Legislation, which examines the effects of raising the minimum drinking level. age.

The lean frame of youth is also characterized by a high head-to-body ratio. When you drink alcohol, it enters your bloodstream and spreads throughout your body. Within five minutes, it reaches your brain, easily crossing the blood-brain barrier that normally protects your brain from harmful substances. "A relatively large proportion of alcohol ends up in the minds of young people, and that's another reason why young people are more likely to get alcohol poisoning," Roodbeen says.

Brainstorming

Important are the changes that occur inside the skull. In the past, neural development was thought to stop in our teens, but a lot of recent research shows that the adolescent brain undergoes rewiring that doesn't end until at least age 25.

The most important changes include a decrease in "gray matter" as the brain removes the synapses that allow one cell to communicate with another. At the same time, white matter - long-distance connections known as axons covered by an insulating fatty sheath - tends to increase. "It's like the highways of the brain," says Lindsay Squeglia, a neuropsychologist at the Medical University of South Carolina. The result is a more efficient neural network that can process information faster.

The limbic system, associated with pleasure and reward, is the first to mature. "These areas are completely adult during adolescence," Squeglia explains. The frontal cord, which is behind the forehead, is slow to mature. This area is responsible for higher-order thinking - which includes emotional regulation, decision-making, and self-control.

At high enough frequencies and levels, adolescent alcohol consumption can impair long-term brain development. Long-term studies show that early drinking is associated with a faster decline in gray matter, while the growth of white matter is slowed. "Those highways don't get paved like kids who start drinking," says Squeglia.

Results may not be immediately apparent in diagnostic tests; in the young brain, regions involved in problem solving may work a little harder to compensate for the deficit. It cannot keep this forever, however. "After many years of drinking, we see less activation in the brain and poorer performance on these tests," says Squeglia.

Early drinking can also affect mental health, and increases the risk of alcohol abuse later in life. This is especially true for people who have a family history of alcoholism - the earlier they start, the more likely they are to develop a drinking problem themselves. Genes associated with increased risk of alcohol abuse appear to have a significant influence during this critical period of brain development. "And the longer a person can wait, the less likely these genes will be activated," says Squeglia.

How can parents' decisions to allow teenagers to drink at home affect them?

How might these findings affect young people's choices - and their parents' decisions about how and when to allow them to drink at home?

"Our message is to delay as much as you can," says Squeglia, "because your brain is still developing, and let your brain grow and be as healthy as it can be before you start getting involved in things like alcohol and substance use."

Whether this advice should be incorporated into law is another matter. Squeglia says that, in his public talks on drinking, audience members often raise the question of "the European drinking model". In some countries such as France, children are allowed to drink a glass of wine or beer to accompany a family meal. Even outside of Europe, many parents believe that the gradual introduction of alcohol in a controlled context teaches young people to drink safely and reduces later binge drinking, where prohibition leads to it being "forbidden fruit".

Much evidence shows that stricter drinking laws, including a lower purchasing age, also encourage more responsible drinking. Consider the study of Alexander Ahammer at Johannes Kepler University Linz in Austria, where anyone over the age of 16 can legally buy beer or wine. If stricter laws only increase the appetite for alcohol, then you'd expect Austria to have a healthier drinking culture than the US - where the minimum legal drinking age is 21. But that's not the case.

Both countries see an increase in over-age drinking. "But the increase was 25% higher in Austria at age 16 than in the US at age 21," Ahammer says.

Waiting, in other words, seemed to encourage more responsible behavior when Americans were allowed to legally buy drinks.

Interviewing his participants about their behavior, Ahammer found that Austrians' perceptions of the dangers associated with drinking changed dramatically when they turned sixteen. "When alcohol becomes legal, young people see it as less dangerous than before," Ahammer says. At the age of 16, that false sense of security can be dangerous, whereas at the age of 21, the more mature the brain can handle its drink.

Nor does the idea of ​​a European healthy drinking culture hold true throughout life. According to the World Health Organization, statistics show that half of all alcohol-related cancers in the European region are caused by light and moderate alcohol consumption.

Based on the scientific evidence, should governments set the minimum legal age at 25 or older - once the brain stops developing? Experts say it's not that simple, as the benefits of public health need to be balanced against people's perceptions of personal freedom.

"I think there's very little public appetite for a 25-year-old drinking age," says James MacKillop, who studies addictive behavior at McMaster University in Hamilton, Ontario. "A higher legal age is considered paternalistic, and it can be seen as hypocritical if the legal age for most people to vote, or the legal age for military service, is 18 or 19."

Ahammer agrees. "Sometimes we just have to let people make their own decisions."

Instead, MacKillop suggests young people can be better educated about the dangers of alcohol, and the ways it can affect the developing brain. "Simply assuming that people will develop responsible behaviors when it comes to these drugs is an optimistic assumption," he says.

Looking back on my youth, I would be interested to know about the ongoing changes in my brain, and the effects my alcohol consumption could have had on its wiring. I don't expect that I'd become an alcoholic — I still drink today, after all, despite knowing the long-term health risks — but I might think twice before buying an extra round.