Aspirin has become the great just-in-case treatment for the West. A little a day is supposed to ward off heart disease, high cholesterol, and mental decline. Actually, strike off that last one.
A study that monitored 6,377 healthy women aged 65 or older, who took 100 mg aspirin every other day for nine years, found that they didn’t fare any better than women who were taking a sugar pill, or placebo.
There was virtually no difference between the two groups in terms of cognition and verbal memory - and each group had the same numbers who suffered substantial decline in their mental abilities. In other words, aspirin didn't have any protective effect.
(Source: British Medical Journal, 2007; 334: 987-90).