Genetics, head injury, and poor nutrition have all been linked to dementia. Scientists are now adding both heavy drinking and abstaining from alcohol to the list, according to a new report.

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Researchers from the French National Institute of Health and Medical Research based in France and the United Kingdom recently conducted a study, published in the British Medical Journal, to determine the relationship between midlife alcohol consumption and risk of dementia into early old age.

To do so, they observed more than 9,000 people, aged 35 to 55, taking part in the Whitehall II Study, which is examining the impact of social, behavioral, and biological factors on long-term health.

The analysts assessed their alcohol consumption and dependence over the course of several years. They then collected hospital records to review the number of participants hospitalized for alcohol-related chronic diseases and cases of dementia.

After analyzing the results, they found both abstinence in midlife and drinking more than 14 units of alcohol a week were both associated with higher risk of dementia, compared to just drinking 1 to 14 units weekly.

In fact, they discovered that heavy drinkers who up their consumption by 7 units a week may have a 17 percent increase in dementia risk.

In the U.K., 14 units of alcohol weekly is the recommended maximum limit, and a unit is approximately 8 grams of alcohol. A standard glass of wine is about 2 units of alcohol and a beer is about 1.75 units.

"[Our findings] strengthen the evidence that excessive alcohol consumption is a risk factor for dementia," the authors said in a statement. "[We] encourage use of lower thresholds of alcohol consumption in guidelines to promote cognitive health at older ages."

They also added their results “should not motivate people who do not drink to start drinking given the known detrimental effects of alcohol consumption for mortality, neuropsychiatric disorders, cirrhosis of the liver, and cancer.”

They now hope for more studies that further explore the effects of light to moderate alcohol in relation to the memory loss condition.

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