"What was the most surprising was the level of association between heavy alcohol use and all types of dementia", says study co-author Dr. Jurgen Rehm.
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Heavy drinking is defined by the World Health Organization and the European Medicines Agency as drinking at least 60 g of pure alcohol daily for men and at least 40 g for women per day, the authors explained.
A new study - the largest of its kind - has found that heavy alcohol use could increase one's risk for all types of dementia, and especially for the early-onset of dementia before 65 years of age.
Lead author Dr Michaël Schwarzinger, of the Translational Health Economics Network in France, said that while the link between dementia and alcohol use needed further research, it was likely a result of alcohol leading to "permanent structural and functional brain damage".
Although women make up the majority of all dementia patients, the study found that almost two thirds (64.9 per cent) of all early-onset dementia patients were men.
Researchers studied a French national database to examine the effect of alcohol disorders, including those diagnosed with mental and behavioural conditions or chronic disease attributable to drink abuse.
The study also showed that the average age of dementia onset differed between men and women.
Most cases of Alzheimer's disease, the most important cause of dementia, happen after the age of 65 and rise dramatically as people age.
Last night experts said even hitting the bottle occasionally can have adverse affects on brain health, warning people to stick to recommended guidelines.
Alcohol use disorders were also associated with all other independent risk factors for dementia onset, including high blood pressure, diabetes, lower education, tobacco smoking, depression and hearing loss.
Over 6% of men and 1.5% of women discharged from hospital had alcohol use disorders, compared to 16.5 % of men and 4% of women with dementia. In a recent review by the Lancet Commission on Dementia Prevention, Intervention and Care, reducing alcohol consumption was not included as one of the nine lifestyle changes that may reduce the risk of dementia. For men, the limit is 7.5 units a day or about three pints of beer, while for women it is five units a day or four small glasses of wine.
We're talking seriously heavy drinking, though. They excluded patients with diseases that could lead to rare dementia and patients with early-life mental disorders.
Medical chiefs in the United Kingdom recommend the consumption of no more than 14 units a week, equivalent to seven pints of average-strength lager or nine 125ml glasses of average-strength wine.
While researchers weren't able to determine why alcohol was the top risk factor, they were able to identify two major pathways as to why that may be.
However, other studies have already discovered that higher amount of alcohol consumption may develop major risk of brain damage and some others have shown that the moderate or light consumption of alcohol provides a potential benefit for cognitive health.