When I turned 50, my friend told me to consider taking an aspirin tablet every day. (Before you react crazily, I should remind you that my friend IS my doctor.) He suggested this routine because aspirin tends to ‘thin the blood’, rendering it more difficult for blood to clot and, therefore, block blood flow to the heart or brain. (Aspirin inactivates platelet cyclooxygenase; this precludes them from producing thomboxane A2. Thromboxane, in turn, is a vasoconstrictor and promotes platelet aggregation. Aspirin also has anti-inflamatory and vasodilation effects.)