Drinking a glass of wine most days of the week can sharpen memory in the over-60s, research has found.
Older people who consume between one and six alcoholic drinks a week have a "significantly" better ability to recall memories of events than those who do not drink at all or who drink a lot more, according to scientists.
Moderate alcohol consumption - up to two alcohol beverages a day - amongst the over 60s was found to preserve the region of the brain responsible for memory and cognition. Younger people considered to be light or moderate drinkers do not benefit in the same way, the study found.
Researchers from the universities of Texas, Kentucky and Maryland in the United States, studied the habits of more than 660 people who completed surveys on their alcohol consumption, took various neuropsychological tests and underwent MRI scans of their brains.
Brian Downer, the lead author of the report, said the amount that people drank in middle age had no bearing on their cognitive functions when they got older.
"This may be due to the fact that adults who are able to continue consuming alcohol into old age are healthier, and therefore have higher cognition and larger regional brain volumes, than people who had to decrease their alcohol consumption due to unfavourable health outcomes," he added.
Findings from animal studies suggest that moderate alcohol consumption may help to preserve hippocampal volume - the area of the brain critical for memory - by promoting generation of new nerve cells.
Exposing the brain to moderate amounts of alcohol may also increase the release of brain chemicals involved with cognitive functions, scientists said.
The study also found that most people drank less in old age than in middle age and that middle-aged men were more likely than middle-aged women to drink heavily.
Those aged over 60 who did not drink at all were less likely to have gone through higher education and were also less likely to have smoked when they were younger.
The amount of alcohol consumption had no impact on overall mental ability.
The report stated: "There were significant differences in cognitive functioning according to late life, but not midlife, alcohol consumption status.
"Patients who were light alcohol consumers during late life had significantly higher episodic memory compared with late life abstainers, whereas no significant differences between moderate and heavy alcohol consumers were detected compared with abstainers."
The findings were published in the American Journal of Alzheimer's Disease and Other Dementias.