crabsallover says 'explains the biochemistry of aspirin simply but well.' my highlights.
by James J. Galligan, Ph.D.,
Aspirin inhibits an enzyme called cyclooxygenase 1 (COX-1) in blood platelets. COX-1 synthesizes factors that cause platelets to clump (aggregate) and clumping platelets form blood clots. Aspirin also inhibits a related enzyme called COX-2. COX-2 accumulates at sites of tissue injury and inflammation. COX-2 is also found in pre-cancerous tissues in the colon called adenomas. COX-2 activity helps to transform adenomas into cancer cells. By inhibiting COX-2 lowly aspirin can help prevent colon cancer.
There are a couple of important additional findings. Firstly, there was a modest dose-related effect. Aspirin doses of 30 mg per day or less had no effect on colon cancer rates while doses higher than 80 mg per day were no better than a dose of 80 mg. The reason this is important is because a major side effect of aspirin therapy is gastrointestinal bleeding. The risk of gastrointestinal bleeding increases with daily aspirin doses more than 80 mg per day. The risk of gastrointestinal bleeding with a daily aspirin dose of 80 mg is small but not zero. Anyone considering daily low doses of aspirin for reducing the risk of heart attack, stroke or colon cancer needs to consult with their doctor first.
Aspirin has been around for more than 100 years. It is inexpensive and if used properly it can help prevent some of the biggest killer diseases. Sometimes the answer is right there in front of us and in the case of colon cancer, aspirin has been sitting there quite awhile.