"This study has shown that drinking alcohol at levels which were believed to be safe is actually linked with lower life expectancy", as well as other health problems, study co-author Dr. Dan G. Blazer II, a professor emeritus of psychiatry at Duke University, said in a statement.
"What this is saying is, if you're really concerned about your longevity, don't have more than a drink a day", said David Jernigan, a Johns Hopkins University alcohol researcher who was not involved in the study.
Experts said it challenged the idea that light drinking was good for us.
The study compared the health and drinking habits of over 600,000 people in 19 countries worldwide and controlled for age, smoking, history of diabetes, level of education and occupation. However, drinking above this limit was linked with lower life expectancy.
If a 40-year-old man dropped his intake from two drinks a day to around five drinks a week, he could expect to add an average of a year or two to his life, the researchers projected.
Drinking between 200-350g alcohol/week would cut up to two years off, and drinking more than 350g alcohol would cut off up to five years.
While the U.S. government now recommends no more than seven drinks a week for women, the recommendation for men is 14 drinks. About 50% of the participants admitted to drinking more than 100 grams per week.
Alcohol guidelines vary substantially from country to country.
The researchers point out that there is no thresholds below which lower alcohol consumption stopped being associated with disease risk but that the threshold for lowest risk was 100g per week.
The researchers examined alcohol's impact on causes of death related to cardiovascular disease, which includes stroke, heart failure, fatal hypertensive disease and fatal aortic aneurysm.
"The take home message is this: less is probably better".
This research recalibrates the concept of moderate drinking and gives a more complicated, nuanced interpretation of how alcohol affects cardiovascular health for better or worse.
Dr Angela Wood, from the University of Cambridge, lead author of the study said: "If you already drink alcohol, drinking less may help you live longer and lower your risk of several cardiovascular conditions".
Although it concluded that alcohol did lower the risk of non-fatal heart attacks, it found that "on balance" there were no health benefits from drinking.
"We should always remember that alcohol guidelines should act as a limit, not a target, and try to drink well below this threshold", said Victoria Taylor, a senior dietitian at the British Heart Foundation.
Men in the U.S. are advised to drink no more than 11 glasses of wine, or pints of beer, nearly double than in the UK.
Reference Wood, AM et al.
The proposed new limits - based on an analysis of data from almost 600,000 drinkers in 19 countries - are significantly lower than the HSE's current guidelines.