No level of regular drinking is without risks to health, the UK's chief medical officers have said as they published a raft of changes to advice on alcohol.
The new guidance sweeps away 1995 recommendations and takes account of new evidence on the increased risk of developing cancer from drinking as well as the harms from binge-drinking.
The guidance says pregnant women should avoid alcohol altogether as there is no evidence for a "safe" drinking level.
Men should consume no more than 14 units of alcohol per week, down from the previous 21 units, bringing them into line with the recommendation for women.
People should have several booze-free days a week but not "save up" their 14 units for a binge.
When drinking on a single occasion, the chief medical officers say people should drink more slowly, consume alcohol with food, and alternate with water.
Furthermore, people should avoid "risky places and activities" and ensure they get home safely to reduce some of the biggest harms from binge-drinking - accidents and injuries.
The new guidance also says evidence that alcohol - such as red wine - is beneficial for health "is considered less strong than it was".
Only women aged 55 and over may benefit from the protective effect of drinking on heart health, the research suggests.
A report informing the new guidance says the risk of getting cancer "starts from any level of regular drinking and rises with the amount being drunk".
Even drinking at low levels is linked to cancers of the lip, oral cavity, pharynx, oesophagus and breast.
At higher levels, there is an increased risk of bowel and liver cancer.
Modelling for the study shows that, compared with non-drinkers, women who regularly drink two units a day have a 16% increased risk of developing breast cancer and dying from it.
Those who regularly consume five units a day have a 40% increased risk.
For every 1,000 women who do not drink, 109 will develop breast cancer. This rises to 126 women for those who drink 14 units or less per week, and 153 women for those who drink 14 to 35 units a week.
Among men, for cirrhosis of the liver, those who regularly drink two units a day have a 57% increased risk of dying from the disease compared with non-drinkers.
Among non-drinking men, 64 in every 1,000 will develop bowel cancer and this stays the same for those drinking 14 units or less per week, but rises to 85 for those drinking 14 to 35 units per week.
For oesophageal cancer among men, six out of every 1,000 non-drinkers will develop it, but this doubles to 13 for those drinking 14 units or less per week and rises to 25 for men drinking 14 to 35 units per week.
The report said drinking regularly over time can lead to a wide range of illnesses including cancers, strokes, heart disease, liver disease, and damage to the brain and nervous system.
Nevertheless, it says drinking 14 unit or less per week keeps "the risk of mortality from cancers or other diseases" - such as liver disease - low.
The new guidance says pregnant women should not drink at all as a precautionary measure, removing the previous clause which said they should drink no more than one to two units of alcohol once or twice per week.
"Despite little evidence of harm from low levels of drinking, it is not possible to say that such drinking carries no risks of harm to the foetus at all," it says.
Chief Medical Officer for England Dame Sally Davies said: "Drinking any level of alcohol regularly carries a health risk for anyone, but if men and women limit their intake to no more than 14 units a week it keeps the risk of illness like cancer and liver disease low.
"I want pregnant women to be very clear that they should avoid alcohol as a precaution. Although the risk of harm to the baby is low if they have drunk small amounts of alcohol before becoming aware of the pregnancy, there is no 'safe' level of alcohol to drink when you are pregnant.
"What we are aiming to do with these guidelines is give the public the latest and most up- to-date scientific information so that they can make informed decisions about their own drinking and the level of risk they are prepared to take."