Life Extension Magazine®

As We See It

Colon cancer: prevention is within reach.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in October 2024. Written by: William Faloon.

William Faloon
William Faloon

There is good and bad news to report about colon cancer. We already know that the disease will kill 56,000 people this year, and that colorectal cancer is the second leading cause of cancer-related death in the United States.

The bad news comes from a study that examined 3,121 asymptomatic people to find out how many of them had neoplastic lesions in the colon that could develop into cancer.1 Examination of the entire colon using flexible colonoscopy revealed a startling 37.5% of these people (average age 63) had one or more neoplastic lesions present. Significant pre-cancerous disease was present in 10.5% of these people with invasive colon cancer present in 1%. Remember this group had no symptoms (such as rectal bleeding) of colon cancer. There was an over-sampling of people with a family history of the disease and most of the participants in this study were men. Those with a family history were about one-third more likely to have colon neoplasms compared to other participants.

This study, showing that 37.5% of asymptomatic people had neoplastic lesions in their colons, prompted The New England Journal of Medicine to write an editorial advocating colonoscopy screening for people over age 50 who are at average risk for colon cancer.2 This editorial emphasized the need of examining the entire colon using flexible colonoscopy as opposed to the lower cost sigmoidoscopy that can only view one-third of the colon.

There are some important facts to know about colonoscopy procedures, but first we want to discuss some good news as it relates to colon cancer prevention. An article appearing a month earlier in The New England Journal of Medicine endorsed several agents to reduce colon cancer risk.3 This article, entitled "Chemoprevention of Colon Cancer" noted that aspirin use reduced colon cancer incidence by 23% to 50%, depending on the dose. The article pointed out that folic acid supplements produced even more significant colon cancer risk reductions of 34% to 75%, depending on how many years the folic acid was taken. Supplementation with calcium produced a modest 15% reduction. Despite the risk reduction benefits of aspirin, folate and calcium, the authors of this chemoprevention article still recommended screening for colon cancer using colonoscopy-type procedures.

There are major reasons why more people are not screened using flexible colonoscopy. For those who don't know, the procedure involves inserting a flexible tube into the rectum and slowly manipulating it through the entire length of the colon. In preparing for the procedure, the patient self-administers laxatives and enemas 12-18 hours before to clean the colon. If a suspicious lesion or polyp is detected during the examination, it can usually be removed by a snipping device inserted through the colonoscope. Because of the pain and discomfort involved, an IV sedative is administered prior to the procedure to almost all patients except people such as myself, who refuse to take the sedatives and instead choose to endure a brief period of agony in order to return to a productive work schedule as soon as the procedure is finished. Most doctors won't perform the procedure without sedatives, but if enough phone inquiries are made, a cooperative "scope-specialist" can often be found. As far as cost is concerned, most insurance companies pay for the procedure if the patient complains about rectal bleeding, otherwise the cash price is usually around $500.00.

In the next two to three years, it is expected that a procedure known as "virtual colonoscopy" will be available that will avoid having to insert the scope through the colon unless a suspicious lesion is first identified. In the meantime, however, colonoscopy is recommended every five to ten years in asymptomatic people and every three years in those with a family history of the disease.

Based on the number of people contracting colon cancer in their forties, The Life Extension Foundation recommends that members over the age of 40 consider colonoscopy examination. In addition to aspirin, folate and calcium supplements recommended in The New England Journal of Medicine article,3 Foundation members should know that curcumin4 and fish oil5 have also been shown to protect against the formation of colon tumors.

The most surprising finding from the latest New England Journal of Medicine study is that about one-third of people over age 50 will develop colon neoplastic lesions that could lead to colon cancer. The good news is that this percentage may be significantly reduced in those who consume the proper supplements, drugs and diet. In most cases, colonoscopy examination will reveal a precancerous lesion before it becomes a lethal metastatic tumor.

Antioxidant protects against kidney damage

When diabetics and others with preexisting kidney disease undergo diagnostic procedures using radiographic contrasting agents, a serious reduction in kidney function often occurs. Doctors theorize this kidney dysfunction is induced by free radicals generated by the contrasting agent.

A recent study showed that when patients consumed just two 600 mg capsules of acetyl-cysteine the day before and two capsules the day of the diagnostic procedure, the risk of kidney dysfunction was reduced more than 10-fold compared to the placebo group.6 In fact, the patients receiving the acetyl-cysteine showed improved kidney function as a group, even after the administration of the toxic contrasting agents. The mechanism of action of acetyl-cysteine was postulated to be its free radical scavenging ability, along with its ability to improve blood flow.

In an editorial that advocated more research on the use of acetyl-cysteine to protect against kidney dysfunction, the doctors pointed out that this antioxidant also shields the liver against acetaminophen toxicity and protects the heart, liver and lungs against ischemic damage.7 (Ischemic damage occurs when there is an interruption of blood flow).

Supplement takers regularly consume antioxidants like acetyl-cysteine (which is the same as n-acetyl-cysteine). It is interesting to note that consuming this antioxidant can protect against some drug toxicities, surgical complications and side effects of diagnostic procedures.

Antioxidants reduce risk of Alzheimer's

Findings presented at the World Alzheimer Congress 2000 revealed that people who consumed the highest levels of antioxidants reduce their risk of contracting Alzheimer's disease by about 25%. The risk reduction was even greater in smokers and those genetically predisposed to develop the disease.

The protective effect was seen in those who consumed vitamin C, vitamin E, beta-carotene and vegetables. Fruit or flavonoids did not confer a benefit in this study. The researchers speculated that antioxidants might reduce the risk of Alzheimer's disease by reducing oxidative stress at a cellular level. This study supports previous human epidemiological research indicating that those who consume antioxidants are less likely to develop Alzheimer's disease as they age.

This data came from an observational study of 5,395 people who are participating in The Rotterdam Study, a longitudinal study of aging. This project began in 1990 with people who ranged in age from 55 to 106 years.

Staying alive

It used to be that the individual had little control over how long they would live. Today's technologies allow humans to play a significant role in determining what their state of health will be. Controllable factors include diet, exercise, supplement use, medical testing and avoiding risks that are known to shorten longevity. Members of The Life Extension Foundation have been enjoying the benefits of a healthier, longer life span for the past two decades. Newly published research continues to substantiate what The Foundation recommended long ago to stave off the degenerative diseases of aging.

For Longer Life

William Faloon Vice President, Life Extension Foundation

References

  1. New England Journal of Medicine; July 20, 2000, pp162-167.
  2. New England Journal of Medicine, July 20, 2000, pp207-208.
  3. New England Journal of Medicine, June 29, 2000, pp1960-1968.
  4. J Surg Res; Apr 2000; 89(2): pp169-175.
    Anticancer Res; Sep-Oct 1999; 19(5A): pp3675-3680.
    Onongene; Oct 1999; 18(44): pp6013-6020.
    Cancer Res; Feb 1, 1999; 59(3): pp597-601.
    J Lab Clin Med; Dec 1997; 130(6): pp576-584.
  5. Cancer Epidemiol Biomarkers Prev; Aug 2000; 9(8): pp819-826.
    Lipids; Feb 2000; 35(2): pp181-186.
    Carcinogensis; Feb 1997; 18(2): pp351-357.
    J Environ Pathol Toxiol Oncol; 2000; 19(1-2): pp81-86.
    CarcinogensisI; DEC 1999; 20(12): pp2209-2218.
    Carcinogenesis; Jun 1998; 19(6): pp 985-989.
  6. New England Journal of Medicine; July 20, 2000, pp180-183.
  7. New England Journal of Medicine; July 20, 2000, pp210-211.