WASHINGTON, 8 August 2007 — Drinking more than three cups of coffee a day helped protect older women against some age-related memory decline, French researchers said on Monday, giving women more reason to love the world’s most popular stimulant. Men did not enjoy the same benefit, they said.
“The more coffee one drank, the better the effects seemed to be on (women’s) memory functioning in particular,” said Karen Ritchie at the French National Institute of Medical Research, whose work appears in the journal Neurology.
The researchers followed more than 7,000 men and women in three French cities, checking their health and mental function and asking them about their current and past eating and drinking habits, their friends, and their daily activities.
They used this information to sort out the specific role caffeine played in these women’s lives. They found that women who drank more than three cups of coffee per day, or its caffeine equivalent in tea, retained more of their verbal and — to a lesser extent — visual memories over four years. These women had a 33 percent lower odds of having verbal memory declines and 18 percent lower odds of having visual and spatial memory declines, compared to women who drank one cup or fewer per day.
The effect also depended on age, with women over 80 reaping more benefits from these beverages than those who were 10 to 15 years younger, Ritchie’s team wrote. It was unclear whether current or former coffee consumption made the difference. Some studies in mice have suggested that caffeine might block the buildup of proteins that lead to mental decline.
Ritchie is not sure why only women benefited in her study. “Our best guess is that women don’t metabolize coffee in the same way (as men),” she said. Ritchie plans to follow the women longer to see if caffeine delays the onset of dementia — the mental confusion that signals Alzheimer’s disease and other brain disorders. She said people should weigh any brain gains derived from caffeine against other effects of the stimulant, including raised blood pressure.
The average American drinks one to two cups of coffee a day, according to the National Coffee Association.
In another study, Italian doctors found that drinking coffee can protect people from developing a tic in which an eyelid twitches uncontrollably.
But people with the condition, known as late-onset blepharospasm, should not try to treat it by downing more java, Dr. Giovanni Defazio of the University of Bari, the study’s lead author, told Reuters. “It is not a cure, but it should prevent the development of blepharospasm,” he said, adding that other researchers need to confirm the findings. Late-onset blepharospasm usually strikes people in their 40s and 50s, and belongs to a class of disorders known as dystonias that involve involuntary muscle contractions. Other types of dystonia include writer’s cramp and musician’s cramp.
Following up on a study that suggested smoking was protective against the development of late-onset blepharospasm, Defazio and his team looked at coffee and cigarette intake in 166 people with the condition, comparing them to 228 hospitalized individuals with a different type of facial spasm and 187 controls.
While there was no link between tobacco intake and the likelihood of developing blepharospasm, people who drank coffee were less likely to have late onset blepharospasm — and the more coffee they drank, the lower was their risk — the researchers report in the Journal of Neurology, Neurosurgery and Psychiatry.
“We don’t know exactly what is in the coffee that has a preventive effect, but the most likely candidate is caffeine,” Defazio said.