This is not the first study to demonstrate that aspirin may slow cancer growth. Most of the other older studies on aspirin, such as the ones cited in the Lancet Oncology review from 2009 have been done on aspirin (and other similar medicine called NSAIDs), have been done on patients with colon cancer and reach a similar conclusion.
"Those taking aspirin were less than half as likely as those who were not to die of prostate cancer over a 10-year period, researchers calculated; the prostate cancer death rate for those taking aspirin was 3 percent, the researchers found, compared with 8 percent for those who did not.
The aspirin users were also significantly less likely to experience a recurrence of prostate cancer or have the disease spread to the bones, the study found.
And taking aspirin, which is usually done for cardiovascular disease prevention, can be risky because it is associated with GI bleeding and hemorrhagic strokes. Nonetheless, for most people, most physicians feel for heart health the benefit outweighs the risk."
So why does aspirin seem to help slow the growth of prostate and colon cancer? Experts believe it has to do with aspirin's ability to reduce inflammation in the body. And an increased inflammatory state is associated with cancer growth. To quote the article again:
"Dr. Otis Brawley, the American Cancer Society's chief medical officer, is quoted as saying, 'Inflammation may not cause a cancer, but it may promote cancer — it may be the fertilizer that makes it grow.'"
"Gold-standard" studies (like randomized controlled trials) have yet to be done, so it's best to not accept the conclusion of these epidemiological studies as the absolute truth. But because so many of these studies reach a similar conclusion, it's hard to ignore the association between taking a daily aspirin and reduced deaths from two very common cancers.
If we believe aspirin slows down the growth of some cancers due to its anti-inflammatory effect, helping people with these cancers live longer, then it is no stretch to believe that foods with anti-inflammatory properties -- like many spices -- can exert a similar effect on these cancers.
This is why Dr. Servan-Scheriber said Indian food and notably Indian spices are anti-cancer in his book.