"There are questions about the dosage, because some people would make stronger coffee than others, so the amount of caffeine can vary per cup," said Zaven Khachaturian, editor in chief of the journal Alzheimer's & Dementia: Journal of the Alzheimer's Association.
He added, "In order to really get a handle on the effectiveness of this for treatment, one needs to have a much larger number of people in the trial."
Study author Ritchie agrees that this is just the beginning. She envisions a future where older women may use a caffeine patch to preserve their minds, but says that a lot of research needs to be done before that time.
"This study opens the door for biologists to look at this question," she said. "To reduce cognitive decline, caffeine is one of the many things we are looking at."