Brain researcher, educator and parenting commentator and educator Nathan Wallis talks to Kathryn about teenagers and drinking. He says the science is clear that alcohol damages the young brain, and he shares tips for parents guiding young people through these years.

The evidence is clear on the impact alcohol has on young brains, says researcher, educator and parenting expert Nathan Wallis - it's very damaging.

He says the damage is done when young drinking starts before the age of 21.

Listen to the full interview with Nathan Wallis

We've got a whole body of research that shows the damaging effects of alcohol to the teenage brain, we still see those effects into people's mid-40s - with some participants, you still see the effects for the rest of their life."

Wallis says if we could "wave a magic wand" and have no one in our society drink alcohol until they were 21 "a 100 percent of our problems with alcohol will disappear".

"When the 45 year old goes out and drinks a dozen cans and goes home and beats up his partner, people think that's the result of the alcohol he's had as a 45 year old, but from a research point of view, if he had not had alcohol until he was 21 a dozen cans wouldn't have wiped out his frontal cortex, it wouldn't have made him lose understanding of consequence. It's because he made it weak by exposing it to alcohol during adolescence."

New Zealand's binge-drinking culture make it difficult to set boundaries for children, he says.

"We've got a culture that celebrates alcohol poisoning."

So how do you guide children onto a safer path? Treat them like they're intelligent, he says.

"If you treat them like they are intelligent, and then they tend to act like they're intelligent. And that means that you include them in decision making, we know from the Dunedin study that the number one factor that determines your outcomes is really self-control.

"So, self-control is what we want them to do when it comes to alcohol, we want them to limit that amount of alcohol, so kids have to be raised being allowed to make decisions or making decisions with you."

This collaborative approach should start early, Wallis says.

"That can be when your kid's two saying 'hey it's snowing today wear your green jersey?' Or are you the sort of parent that says 'hey it's snowing today would you like to wear your green jersey or your blue jersey?'

"So even though the kid's two he's already making decisions."

That approach is a sound foundation for the teenage years, he says…

Go to this episode on rnz.co.nz for more details