When you decide to give up alcohol for a month, it's natural to worry that your resolve won't stand up to the test.
But for women embarking on dry January, it's not their own ability for self-restraint they have to worry about - it's their partner's.
Men are a bad influence on their other halves when it comes to alcohol consumption, experts say. They can even sabotage a woman's efforts by suggesting they drink more.
Researchers found that 29 per cent of women confessed they would drink far less if it wasn't for their partner. This is almost twice the number of men - 16 per cent - who said their alcohol intake would be lower if they were single.
A third of men admitted they actually encourage their other halves to have just one more drink - even when they've had enough.
By comparison, only 15 per cent of women said they try to press extra drinks on their reluctant partners.
The study of 2,000 adults by Drinkaware, an independent body which runs alcohol awareness campaigns, comes as millions of people are trying to stay alcohol-free as part of dry January.
There is growing evidence that going teetotal even for a short period can help lower blood pressure, encourage weight loss and repair previous liver damage.
The survey also found that 40 per cent of men and 15 per cent of women drank more than the safe level of alcohol, which is about 14 units a week. This equates to six pints of 4 per cent beer or six glasses of 13 per cent wine.
But the true figures may be even higher, as many adults underestimate their consumption, as they forget how much they've had.
Elaine Hindal, chief executive of Drinkaware, said: 'We know that couples who are planning a health regime together fare better when they really support each other.'
Joanna Simons, chief executive of Alcohol Concern, added: "It is really important for everyone to understand how much they are drinking, and to be aware of the safe limits when it comes to alcohol.
"Now is a great time to get a bit of help with cutting down your alcohol intake by signing up to our Dry January campaign, and encouraging partners, friends and family to take part too.
"Research shows that even a month off the booze makes a big difference to your health, saves money and helps get rid of those extra Christmas pounds."