Be careful if you take aspirin regularly. If you develop bleeding from something like diverticulitis, doctors may take you off of it suddenly but that significantly increases your risk of stroke which is what I think may have happened with my mom.
Plus, the cardiologist said that aspirin isn't really a blood thinner but an anti-inflammatory. (Don't quote me, I'm just repeating what he said when I asked if there were alternatives.)
Something better to try might be garlic or low dose vitamin E. I think those actually do thin the blood. (Again, don't quote me. I'm not one of the bio-techy brainy people here at PR.)
Asprin as a blood thinner is i guess the laymans terms but it stops platelets aggregation ie playelets becoming sticky, which could form clotts??