Wednesday August 15, 2007 (Foodconsumer.org) -- Patients who had received surgery and chemotherapy for state III colon cancer would be better off eating a so-called prudent diet as researchers found that eating a Western diet would increase the risk of cancer recurrence.

A Western diet is rich in processed and or red meat, fat, French fried, refined, grains and sweets while a prudent diet is full of fruits and vegetables, poultry, and fish.

Researchers found those with high intake of a Western diet were at a much higher risk of cancer recurrence compared to those who ate less of a Western diet.

The study was conducted by Jeffrey A. Meyerhardt, M.D., M.P.H., of the Dana-Farber Cancer Institute, and colleagues and published in the Aug. 15 issue of the Journal of the American Medical Association (JAMA).

For the prospective study, the researchers followed 1,009 patients with stage III colon cancer who were enrolled in a randomized adjuvant chemotherapy trial from April 1999 through May 2001.

The study meant to investigate the effect of dietary patterns on the recurrence of colon cancer although early epidemiologic studies have found associations between dietary factors and the risk of developing colon cancer.

The researchers hypothesized that increased intake of meat, high fat and processed foods in the Western diet may facilitate a milieu that allows the residual "disease" to proliferate and spread.

Other possibilities include that patients who ate high amounts of the Western diet after diagnosis may have had a similar dietary habit prior to diagnosis, resulting in more biologically aggressive cancer.   But no association between dietary patterns and tumor related characteristics was observed, the researchers said.

For the study, patients were surveyed by a food frequency questionnaire during and six months after adjuvant chemotherapy.

The researchers used factor analysis to sort out two major dietary patterns, the fat-loaded Western diet and the prudent diet.   And then they examined the data to see if the dietary patterns were associated with the cancer recurrence or death in patients with stage III colon cancer.

During the 5.3-year study, 324 patients had a cancer recurrence, leading to 223 deaths.   28 patients died without recorded cause.

Those who were in the highest quintile of the Western diet were 3.25 times more likely to have a cancer recurrence or death compared to those who were in the lowest quintile of the Western diet, the study found.

Colon cancer patients in the highest quintile were 2.9 times more likely to have a cancer recurrence and 2.32 times more likely to die compared to those in the lowest quintile.

Various intakes of the prudent dietary pattern, however, did not seem to affect the recurrence-free survival or overall survival.

Patients in the highest quintile of the prudent diet were 1.20 times more likely to have disease-free survival, compared to those who were in the lowest quintile.

Those who had highest intake of the prudent diet were found to be physically active, have a lower BMI six months after adjuvant therapy and be less likely smokers.

Based on the data, the researchers suggest eating more red and processed meat, French fries, sweets and desserts, and refined grains increases the risk of cancer recurrence and decreases survival.

What is not clear enough is how worse a Western diet is than the prudent diet?   The study seemed to have compared only effects of each dietary pattern.   No detail was reported on comparison between the Western diet and the prudent diet.

As one likely eats more of the prudent diet if he eats less of the Western diet, meaning that the prudent diet should be better than the Western diet when it comes to prevention of cancer recurrence in colon cancer patients.

According to the National Cancer Institute, more than 111,000 new colon cancer cases are diagnosed and more than 52,000 will die each year from the disease.

In response to the study news, the American Institute for Cancer Research (AICR) published a press release to emphasize the importance of plant foods in prevention of colon cancer.  

The AICR recommends "colon cancer survivors follow the dietary advice known to reduce risk for colon cancer and cancer in general: aim for a diet high a variety of vegetables, fruit, whole grains and beans and low in meat and dairy foods."