Why Aspirin Can Prevent Cancer
Researchers from Italy’s Nuovo Regina Margherita Hospital have found that low-dose aspirin can prevent colorectal cancer. Why? Doesn’t aspirin cause stomach bleeding, ulcers, blood thinning and other problems?
The researchers analyzed medical records of 100,000 human subjects starting from fifty years of age until they died. The study utilized 10-year colonoscopy or sigmoidoscopy screening records, together with the patients’ charts that indicated whether they were taking low dose aspirin or not (as many older patients with heart issues are advised to take low-dose aspirin as a blood-thinner).
Those patients that took low-dose aspirin were significantly less likely to contract colorectal cancer. Those taking the low-dose aspirin that were getting colonoscopies had their cancer prevention rates increase from 68% to 81%, and those receiving sigmoidoscopy screening had cancer prevention rates increase from 39% to 69%.
The researchers commented that, “When assuming a suboptimal efficacy of endoscopy in preventing CRC, the addition of low-dose aspirin may be an effective and cost-effective strategy, mainly because of its high efficacy in preventing proximal colorectal cancer.”
In another recent study, aspirin was found to also reduce the incidence of Hodgkins lymphoma. The study of Denmark patients by researchers from the Cancer Prevention Institute of California found that low-dose aspirin use decreased Hodgkins compared with the general population in Denmark.
However, this anti-carcinogenic effect was not found for other NSAIDs, including selective cyclooxygenase-2 (sCOX-2) inhibitors, and others. Only aspirin had this effect. Low-dose aspirin use over a seven year basis decreased Hodgkins by 35% according to the data, while selective COX inhibitors increased the risk of Hodgkins by 27%.
Why Aspirin has Positive Effects
Why is aspirin, known for various side effects such as gastrointestinal bleeding and ulcers, anti-carcinogenic?
Acetylsalicylic acid or aspirin is a synthetic molecule designed to mimic the effects of salicin, originally derived from willow bark and meadowsweet herb. For thousands of years, herbalists and ancient healers used both willow bark and meadowsweet for the relief of pain, inflammation, the relief of gastrointestinal upset, nausea, heart issues, rheumatism and many other disorders. With these sorts of effects there is no surprise some of its constituents might be anti-carcinogenic.
Willow bark has a long history of clinical use. It has been used by traditional physicians for over five thousand years for pain, rheumatism and inflammation. Sumerian Clay tablets some 4,000 years ago documented using willow leaves to treat fever and rheumatism. The 2500-3000 B.C. Ebers-Edwin Smith Surgical Papyrus—translated by James Breasted in the 1920s—documented the use of willow by the “Father of Medicine,” Imhotep. He used willow for healing wounds and inflammation. The ancient Chinese also used willow to treat pain, wounds, goiter, hemorrhaging, and rheumatic fever. The ancient Greek physicians also used willow. Hippocrates, Celsius, Pliny the Elder, and Galen all recommended willow for pain and inflammation. Early western European physician and herbalist Dioscoridies also documented its use for pain and inflammation.
In 1828, salicin was isolated from the bark of the willow tree by Joseph Buchner. Two years later, salicin was isolated from the flower of the meadowsweet plant by Johann Pagenstecher. In 1838, a method of isolating salicylic acid from willow extract was discovered by the Italian Raffaele Piria. Meanwhile, German chemist Karl Jacob Lowig extracted the same salicylic acid from meadowsweet extract. In 1874, salicylic acid began to be produced for commercial use. Twenty-three years later, in 1897, Charles Garhardt, a chemist at the Friedrich Bayer & Company, synthesized a similar derivative by adding an acetyl group (OCOOH), to produce the more stable acetylsalicylic acid. The Bayer company proceeded to call it aspirin and began large-scale production.
Aspirin’s mechanism of action in the body continued to be mysterious, however. Finally, in 1971, Sir John Vane determined that acetylsalicylic acid inhibited prostaglandin synthetase (later identified as cyclooxygenase), producing its anti-inflammatory and anti-thrombosis effects. Sir John Vane received the Nobel Prize for Medicine in 1982 for this hypothesis.
Like willow and meadowsweet, aspirin has an immediate effect to reduce pain. Aspirin and natural salicin bind to cylooxygenase-2 within the cells. This blocks the pain and inflammation cascade. Cylooxygenase-2 produces prostaglandins that in turn send messages to the brain that a particular part of the body is injured. When cylooxygenase-2 is blocked, the process of converting arachidonic acid to prostaglandins is halted.
Cylooxygenase-2 also stimulates the production of thromboxanes. These stimulate the process of blood clotting within the platelets—called platelet aggregation. This is again part of the healing process, because if a blood vessel were to be pierced, our blood would leak out, causing immediate death unless the vessel was sealed somehow. In other words, thromboxanes stimulate clotting, preventing our bodies from bleeding to death.
Side effects of the Synthetic Version
This later effect also produces the side effect that aspirin is also known for—as a blood thinner. Because many heart attacks, strokes and other cardiovascular problems are caused by blood clots, low-dose aspirin is used to keep the blood thinner than normal for those with unhealthy artery health.
Aspirin’s blood-thinning effects have their benefit, but they can also create internal bleeding from a variety of internal injuries. The dangerous part of this is that the person may be bleeding internally without knowing it.
The problem with acetylsalicylic acid, because of its isolated and synthetic nature, is that its positive effects come with a price of several other adverse effects. Aspirin is notorious for damaging the lining of the stomach, and causing a variety of digestive issues, including acid reflux, ulcers, nausea and gastritis. Aspirin has also been known to produce some liver toxicity, Reye’s Syndrome (especially in children), and tinnitus—ringing of the ears.
The Bottom Line
The reason for some of aspirin’s benefits is that it is based upon a natural molecule with natural health benefits. The reason for aspirin’s unhealthy and sometimes dangerous side effects is because the salicylic molecule has been separated from the natural buffering molecules present in willow, meadowsweet and similar herbs. These herbs have hundreds of constituents, and salicin is only one of them. Studies have indeed shown that natural salicin from these herbs has every bit of pain-relieving ability as aspirin and other COX-inhibitors. These natural herbs also contain other molecules that buffer the negative side effects of isolated salicylic acid. In other words, meadowsweet and willow do not have these negative side effects, because of the various buffering agents present in nature’s version.
You see, nature is quite intelligent. Far more intelligent than our attempts to copy it have been.
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