Chief Medical Officer Sir Liam Donaldson has warned that a "laissez-faire" stance adopted by some parents towards their children's drinking is jeopardising the health of their offspring.
He said allowing teenagers to consume alcoholic drinks with their friends could be "storing up" problems for later life, while middle-class families are "misguided" in diluting their children's wine.
Sir Liam said parents should not expose children to family events where drinking is the central activity, and ideally should not allow youngsters in "alcohol-fuelled environments".
Yet parents could show their children that - if alcohol is drunk at home - it is consumed in a "positive" setting such as a family meal.
Sir Liam, who this week announced his intention to step down as chief medical officer for England, said one of the risk factors for children drinking was parents having a "laissez-faire approach to a child drinking or getting drunk".
The idea that if you "somehow wean children onto alcohol at an early age they won't have any problems in later life, they will be sensible, is not supported by evidence", he added.
In fact, studies have shown the opposite - that those who begin drinking early are more likely to binge drink in their teenage years and develop alcohol-related problems later in life.
"The more they get a taste for it, the more likely they are to be heavy drinking adults or binge drinkers later in childhood," Sir Liam said.