(WDP) - A pint of beer or medium glass of wine a day can protect against an early death from Alzheimer's , according to a new study.

Those who drank moderately of between two to three units had lower death rates than those who were teetotal, drank a unit or less or drank more.

It found moderate drinking was associated with a 77 per cent lowered risk of death compared with a tally of one or fewer daily units.

There was no significant difference in death rates among those drinking no alcohol or more than three units every day compared with those drinking one or fewer daily units.

However increased alcohol intake is only protective until a certain consumption level.

While a daily tipple has been shown to lower the risk of developing and dying from heart disease and stroke, alcohol damages brain cells and might be harmful.

The Danish study was one of the first to show an association between levels of drinking and death from Alzheimer's disease (AD) .

Previous research has shown light to moderate drinking reduces the risk of dementia and cognitive decline, "virtually no attention has been paid to the effect of alcohol consumption in patients with AD."

Dr Sine Berntsen of the University of Copenhagen said: "It has been argued that social drinking may be harmful for patients with AD.

"However, we have not been able to identify any studies on the association
between alcohol consumption and mortality in patients diagnosed with dementia.

"Considering that AD is a neurodegenerative disorder and that alcohol has known
neurotoxic effects, one could easily jump to the conclusion that alcohol is damaging for patients with AD.

"The aim of this study was to investigate whether the positive association between moderate alcohol intake and mortality shown in population-based studies on healthy subjects can be transferred to patients with mild AD."

The study published in the online journal BMJ Open examined levels of drinking in 321 people with early stage Alzheimer's disease as part of the Danish Alzheimer's Intervention Study (DAISY).

Around one in 10 (8%) drank no alcohol and at the other end of the scale, around one in 20 (4%) drank more than 3 units daily.

Most of the sample (71%) drank one or fewer units a day and 17% drank 2-3 units.

A sixth died over the three year follow up period.

Dr Berntsen said: "In this study in patients with dementia, we found that in abstinent
patients and in patients with high alcohol intake there was no significant increase or decrease in mortality.

"An association that is suggestive of a protective effect between alcohol and mortality was seen only in the group of patients who had 2-3 units a day."

The study noted small amounts may have a health preserving effect or patients with moderate alcohol intake may have a richer social network improving both quality and length of life.