Of those who had obtained alcohol in the last four weeks, they were most likely to have been given it by their parents, at 71%.
Elsewhere, friends provided alcohol on 49% of occasions, while those surveyed said they had taken it from home without permission at 48%.
The data found 13% of children aged 11 to 15 from the wealthiest third of families had consumed alcohol in the past week, compared with 7% of children from the same age group in the least wealthy third.
Andrew Misell, a director at Alcohol Change UK, has warned against children drinking with their parents – a practice he has called “European drinking” – as it is more in tune with the culture in countries like France and Italy where children are introduced to wine from an early age.
Parents – particularly those who are more affluent – may be introducing children to alcohol in the belief it emulates a more ‘European’ style of drinking, Misell told Yahoo UK.
“We’ve known for a long time that parents are the main source of alcohol for underage drinkers,” he said.
“Some parents seem to believe that it’s a good idea to introduce their children to alcohol – that it’s a normal part of social life and one they need to learn about.
“One variation on this second idea, perhaps in more affluent families, is the belief that our European neighbours avoid many alcohol problems by introducing children to alcohol early on.”
Children drinking alcohol at home
While popular series such as ‘The Inbetweeners’ and ‘Skins’ might portray underage teenage drinking away from the prying eyes of parents, outside of the home in parks and at parties, the results show it is apparently more common in the home.
Two-thirds of children said they had consumed alcohol at home, with 41% claiming they had drunk it at someone else’s house.
Children drinking at home is legal. According to UK law, it is legal for children aged five and over to drink alcohol at home or on other private premises.
But is it safe for parents to permit them to do so?
British drinking culture ‘not the same’ as in Europe
Letting children and teenagers drink at home may be putting them “at risk” of unhealthy drinking habits, said Misell.
“In reality, the amounts of alcohol given to children in the wine-drinking countries of Europe are very small; and children’s introduction to wine occurs as part of an overall moderate drinking culture.
“The situation in the UK is very different, and there is a real risk that by introducing children to alcohol we are simply assisting them to join in with British drinking culture rather than some Continental ideal.”
Does teenage drinking with parents promote a ‘moderate’ attitude?
Misell also suggests some parents may give children alcohol in order to promote a more moderate attitude to drinking – “to stop them seeking out stronger drinks and consuming them unsupervised”.
However, there is still some evidence to support the practice, with a 2010 study finding Italian youths whose parents let them have alcohol with meals growing up are less likely to be problem drinkers in later life.
Alcohol-free child ‘the best option’
Avoiding alcohol during childhood and early adulthood is best to avoid health risks, argues Drinkaware’s Chief Medical Advisor Dr Fiona Sim.
She told Yahoo UK: “Alcohol is harmful to children, which is why the UK Chief Medical Officers say an alcohol-free childhood is the best option.”
She highlights short-term danger that can lead to hospitalisation, such as “acute alcohol poisoning, which can cause low blood sugar, seizures, and can be fatal, greater chance of accidental injury, of being involved in violence and of ending up in vulnerable or dangerous situations”.
Highlighting longer-term health risks, she added: “Drinking regularly during childhood and young adulthood can cause permanent brain and liver damage to these developing organs, and children's educational attainment can be adversely affected, resulting in lifelong negative impact on their potential.
“People who start drinking at a young age are also more likely to have alcohol problems as an adult. They are also more likely to have problems with their mental health, use of illegal drugs and tobacco.”
‘Little research’ to support teenagers drinking with parents
An earlier study found one in six British parents let their children drink alcohol by the age of 14 – and well-educated parents of white children were the most likely to permit this practice.
Yet there is “little evidence” to prove this is effective, said the study’s lead author Professor Jennifer Maggs from the Centre for Longitudinal Studies at the UCL Institute of Education.
“Parents of socially advantaged children may believe that allowing children to drink will teach them responsible use or may in fact inoculate them against dangerous drinking. However, there is little research to support these ideas,” she explained.
What to do if you are concerned about your teenager’s drinking habits
For parents concerned about their children’s drinking, Sim says the best solution is to start an open dialogue in the home.
READ MORE: There are five types of problem alcohol drinkers
“We would encourage parents, guardians and teachers to talk openly with children about the serious risks associated with drinking as soon as they could be exposed to alcohol, either in or outside the home,” she said.
How parents’ drinking habits affect children
Parents may also endeavour to reduce their own drinking habits in order to prevent their children developing a risky drinking habit,” Sim suggested.
Drinking habits can be assessed using the Alcohol Use Disorders Identification Test (AUDIT) score, which ranges between 0 and 12. These behaviours may include drinking, starting drinking at a younger age, drinking frequently, being drunk and experiencing negative consequences as a result of drinking.
Those parents who have a higher AUDIT score are more likely to have children who in turn have an unhealthy attitude to alcohol, explained Sim.
“For example, 51% of children with parents/guardians in AUDIT zones 2-4 have themselves been drunk (compared to 42% of children with parents/guardians in zone 1), and they are also more likely to have experienced a negative consequence from drinking (40% versus 22%),” she said.