Evidence for the health benefits of aspirin has mounted during the last few years. Medical researchers have touted daily aspirin, or acetylsalicylic acid, as an inexpensive and highly effective way to lower rates of stroke, heart attack, colon cancer, prostate cancer, and even Alzheimer’s disease. Many of the positive effects of aspirin derive from its anti-inflammatory and blood-thinning properties. Although daily aspirin use seems to provide an array of health benefits, it also may be associated with serious side effects, such as gastrointestinal bleeding. For this reason, patients should not take daily aspirin unless the benefits strongly outweigh the potential risks.
Aspirin reduces inflammation, prevents blood clotting, reduces fever, and alleviates pain. Through its acetyl group, aspirin binds to the enzyme, cyclooxygenase, thereby blocking the production of prostaglandins and thromboxanes. Prostaglandins narrow blood vessels, promote blood clots, increase nerve sensitivity to pain, and cause fever and inflammation in the body. Thromboxanes increase the blood pressure, promote blood clots, and constrict blood vessels. By blocking the production of these hormone-like chemicals, daily aspirin opens up blood vessels, lowers the blood pressure, and prevents blood clotting, reversing the physiologic conditions that contribute to heart attack and stroke.
Scientists have studied whether daily aspirin use may inhibit the growth of some forms of cancer. Researchers have found patients with colon cancer who took daily aspirin had higher survival rates than those who didn't. Other researchers have found that death rates of a variety of cancers were significantly reduced in daily aspirin users.
Clinical studies support the use of aspirin for Alzheimer’s disease prevention. In those patients who take an aspirin daily, there was a 40 percent reduction in incidence of Alzheimer’s disease relative to the general population. Scientists do not know why aspirin has this apparent protective effect, but it is possibly related to improvements in brain blood flow due to reduced clot development and more widely dilated blood vessels associated with daily aspirin use. In the elderly, however, the possible reduction in risk for Alzheimer’s disease from regular aspirin use must be weighed against the increased risks of intracranial bleeds and hemorrhagic stroke associated with daily aspirin.