A steady drip, drip, drip of research has suggested in recent years that caffeine may have some protective effect against Alzheimer’s disease. That research received an extra jolt Sunday with the publication of two new studies.
Both studies involved mice genetically bred to develop symptoms of Alzheimer’s disease when they aged. One study found that the animals’ memory problems reversed after they were fed 500 milligrams of caffeine (the equivalent of five 8-ounce cups of “regular” coffee or two coffee-shop lattes or cappuccinos) daily for two months. In fact, their performance on memory tests became identical to the performance of other mice without dementia.
The second study revealed that these elderly caffeinated mice also exhibited a 50 percent reduction in their brains of the sticky beta amyloid plaques that are a hallmark of Alzheimer’s disease.
The studies’ authors believe — but have yet to prove — that caffeine reduces enzymes and inflammatory changes in the brain that can lead to the overproduction of beta amyloid.
In both studies, which were published in the July 5 online edition of the Journal of Alzheimer’s Disease, the mice were 18 to 19 months old — the human equivalent of about 70 years — when they began drinking caffeine. The same University of Florida researchers who conducted these studies had earlier reported that mice bred to have Alzheimer’s disease were protected against the onset of memory problems in old age if they began drinking caffeine regularly in early adulthood.
These findings do not mean that all of us should start downing caffeine daily. Although studies using genetically bred mice models are extremely helpful for the study of human disease, their results do not always hold up when the same studies are conducted with humans. Also, caffeine has its health risks. In addition to causing such symptoms as anxiety, stomach upset, and sleep problems, it’s also been linked to an increased risk of high blood pressure and, in pregnant women, of miscarriages.
Still, this may be promising news for those of us with a morning caffeine habit.