The average bottle of wine contains 10 units of alcohol
Parents of young children are being warned about their drinking habits after a poll found their consumption had reached worrying levels.
The survey of nearly 2,000 people found half of 25 to 44-year-olds drank due to stress - the highest of any age group.
Experts said they were particularly vulnerable at the moment with the holiday season drawing to a close and children returning to school.
The poll was done for the government's Know Your Limits alcohol campaign.
It found 42% of all drinkers - 45% of men and 40% of women - drank to cope with stress.
But in the over 55s age group just 30% cited this reason, compared with 51% of 25 to 44-year-olds.
Overall, two thirds drank at least once a week with a quarter hitting the bottle at least four times a week.
The research coincided with a separate poll of 3,000 mothers by the Netmums website. It found that 49% of mothers drank at home at least three or four nights a week.
Of those that drank more than government guidelines - two to three units a day - 81% did so to wind down from a stressful day.
Experts pointed out that a bottle of wine contained about 10 units which if shared between a couple would put both over the recommended daily limit.
Siobhan Freegard, of Netmums, said: "The extent to which this research showed modern mums are drinking really surprised us.
"It shows many mums and dads are developing a 'bottle a night' habit without really thinking about the health consequences.
"Getting used to juggling work and home life again after the summer break can be stressful for parents, but it's important not to allow yourself to slip back into the routine of relying on alcohol to help you unwind."
And Dr Sarah Jarvis, a GP who is involved in the joint Home Office and Department of Health Know Your Limits campaign, added: "If you're returning to work, turning to the bottle can actually increase your stress levels.
"Try exercise or a nice warm bath to unwind instead. Regularly exceeding the guideline alcohol limits can increase your risk of several forms of cancer, heart disease and stroke."