A month off alcohol could help prevent serious illnesses in later life, the Press Association reports.
Patients who gave up for four weeks saw benefits for their liver function, blood pressure and cholesterol levels and were also at lower risk of developing diabetes and liver disease, research from University College London suggested.
Those who took part in the month of abstinence also lost weight and reported improvements in their concentration and sleeping.
Professor Kevin Moore, who co-authored the study, told the Press Association: "If you took a drug that reduced blood pressure and improved cholesterol and insulin resistance it would be a blockbuster drug that would be worth billions."
The women had been drinking an average of 29 units of alcohol a week, equivalent to more than four units a day, while the men were typically on 31 units - both above government guideline levels.
After four weeks their "liver stiffness" – an indication of damage and scarring – had been reduced by 12.5%, and their insulin resistance – a measurement of diabetes risk – had come down by 28%.
Prof Moore, a liver specialist, said: "These subjects were probably average drinkers - they drank in excess of the guidelines. We studied them before and after the dry month.
"There was certainly substantial improvement in various parameters of the liver. The other parameters, blood pressure, cholesterol, how well the subjects slept were also substantial."
Prof Moore added public health bodies should be "very interested" in the study but said more work needed to be done to establish the lasting effects of abstinence.
"Does it have a sustained impact? We think we will find people drink less going forward.
"The next thing would be to extend the dry January beyond one month to two months, three months."
Gautam Mehta, a liver specialist who oversaw the study, told the Daily Mail: "I am excited. There are some findings that will be pretty novel. It's an important study which shows the benefit from a month's abstinence. What we can't say is how long those benefits are, how durable those benefits are."
Current official guidance states men should not regularly exceed four units a day, while women should not have more than three units although they are subject to a government review could be published later this year.