Red meats and animal fats do NOT cause cancers -- study

[doreen T]

Two years ago .. October 2001 .. the headlines at CNN, AOL, MSN, major newspapers, TV etc etc all carried the dire warning that diets high in meat and/or saturated fat caused, or were linked to, cancer of the stomach and esophagus!!!!

We posted and discussed the fallacies and inconsistencies of those "studies" here in the Research/Media forum. FWIW, the reports weren't based on actual scientific study. Instead, telephone interviews with cancer patients or in many cases their survivors were conducted with a questionnaire about dietary preferences .. • Animal fat ups risk of stomach, esophageal cancer (http://forum.lowcarber.org/showthread.php?t=23634) .. from October 2001

• Here we go again -- Study links meat consumption with cancer risk (http://forum.lowcarber.org/showthread.php?t=28007) .. from December 2001

There were many flaws in those reports, including the fact that hotdogs and processed lunch meats were deemed to be "red meats" .. and "high fat diet" included chips and margarine. Plus, "high fat high meat" diets were also high in refined sugar, starches and white bread.

I also noted at the time the finding which suggested that increased consumption of fish, vegetables and fruits seemed to be protective against these cancers .. yet this point was never really picked up by the media. :rolleyes:

OK, scroll ahead to the present. In last week's issue of the Journal of the National Cancer Institute, the results of a long-term study showed the greatest risk factor for these cancers are:history of smoking
alcohol
obesity
esophageal reflux (untreated)
dietary nitrates *
lack of vegetables and fruits **


MEATS AND FATS DO NOT APPEAR ON THE LIST AS RISK FACTORS. PERIOD.

note* - dietary nitrates come from processed smoked foods (not just meats). But also .. excess nitrates in drinking water are a big concern in many parts of the world where untreated agricultural waste is polluting the water supply.

note** - the significance of vegetables and fruits may be more a feature of their antioxidant and phytonutrient content than their fiber content. Which is likely why grains and cereals aren't mentioned.


The report is posted below .. and also the journal abstract of the study.



Doreen

[doreen T]

A few main risk factors account for stomach cancer

Last Updated: 2003-09-19 16:08:16 -0400 (Reuters Health)

NEW YORK (Reuters Health) - A few main risk factors account for most stomach and esophagus cancers that occur in the general population, new research shows.

Although numerous reports have identified risk factors for these diseases, "no study has comprehensively examined their contributions to the cancer burden in the general population," lead author Dr. Lawrence S. Engel, from Memorial Sloan-Kettering Cancer Center in New York, and colleagues note.

The current study involved 1143 patients with esophagus or stomach cancer and 695 healthy people. The patients were diagnosed between 1993 and 1995 in Connecticut, New Jersey, or Washington.

The researchers looked at the four main types of cancer that involve the esophagus and stomach: adenocarcinoma of the esophagus, squamous cell cancer of the esophagus, adenocarcinoma of "cardia" region of the stomach, and adenocarcinoma of other stomach areas.

The new findings are reported in the Journal of the National Cancer Institute.

Being overweight accounted for the greatest percentage of esophagus adenocarcinomas--41 percent, the authors state. The next biggest contributor--ever smoking--accounted for 40 percent of cases. Together, being overweight, ever smoking, reflux of stomach contents into the esophagus, and low fruit and vegetable consumption accounted for 79 percent of cases.

Alcohol consumption was responsible for the greatest percentage of esophageal squamous cell cancers--72 percent. Nearly 90 percent of cases could be accounted for by alcohol use, a history of ever smoking, and low fruit and vegetable intake.

For stomach cardia adenocarcinomas, smoking was the biggest contributor, responsible for 45 percent of cases. A history of ever smoking and being overweight together accounted for 56 percent of cases.

For other stomach adenocarcinomas, increased nitrite intake, a compound found in smoked foods, accounted for the greatest percentage of cases--41 percent, the researchers point out.

The rapid rise in the rate of new cases of stomach and esophagus cancers that has occurred in Western populations appears to result from increases in the prevalence of several risk factors that people are capable of changing, the authors note.

"Efforts to reduce the prevalence of being overweight, having gastroesophageal reflux, and smoking and to improve diet could reverse this troubling cancer trend," they add.

SOURCE: Journal of the National Cancer Institute, September 17, 2003.


http://www.reutershealth.com/archive/2003/09/19/eline/links/20030919elin018.html

[doreen T]

Population Attributable Risks of Esophageal and Gastric Cancers

< snipped authors' affiliations >

Background: Several risk factors have been identified for esophageal adenocarcinoma, gastric cardia adenocarcinoma, esophageal squamous cell carcinoma, and noncardia gastric adenocarcinoma, but no study has comprehensively examined their contributions to the cancer burden in the general population. Herein, we estimate the population attributable risks (PARs) for various risk factors observed in a multicenter population–based case–control study.

Methods: We calculated PARs by using 293 patients with esophageal adenocarcinoma, 261 with gastric cardia adenocarcinoma, 221 with esophageal squamous cell carcinoma, 368 with noncardia gastric adenocarcinoma, and 695 control subjects. We included smoking for all four tumor types and Helicobacter pylori infection for noncardia gastric adenocarcinoma as established causal risk factors as well as several other factors for which causality is under evaluation.

Results: Ever smoking, body mass index above the lowest quartile, history of gastroesophageal reflux, and low fruit and vegetable consumption accounted for 39.7% (95% confidence interval [CI] = 25.6% to 55.8%), 41.1% (95% CI = 23.8% to 60.9%), 29.7% (95% CI = 19.5% to 42.3%), and 15.3% (95% CI = 5.8% to 34.6%) of esophageal adenocarcinomas, respectively, with a combined PAR of 78.7% (95% CI = 66.5% to 87.3%). Ever smoking and body mass index above the lowest quartile were responsible for 45.2% (95% CI = 31.3% to 59.9%) and 19.2% (95% CI = 4.9% to 52.0%) of gastric cardia adenocarcinomas, respectively, with a combined PAR of 56.2% (95% CI = 38.1% to 72.8%). Ever smoking, alcohol consumption, and low fruit and vegetable consumption accounted for 56.9% (95% CI = 36.6% to 75.1%), 72.4% (95% CI = 53.3% to 85.8%), and 28.7% (95% CI = 11.1% to 56.5%) of esophageal squamous cell carcinomas, respectively, with a combined PAR of 89.4% (95% CI = 79.1% to 95.0%). Ever smoking, history of gastric ulcers, nitrite intake above the lowest quartile, and H. pylori infection were responsible for 18.3% (95% CI = 6.5% to 41.8%), 9.7% (95% CI = 5.4% to 16.8%), 40.7% (95% CI = 23.4% to 60.7%), and 10.4% (95% CI = 0.3% to 79.6%) of noncardia gastric adenocarcinomas, respectively, with a combined PAR of 59.0% (95% CI = 16.2% to 91.4%).

Conclusion: In this population, a few known risk factors account for a majority of esophageal and gastric cancers. These results suggest that the incidence of these cancers may be decreased by reducing the prevalence of smoking, gastroesophageal reflux, and being overweight and by increasing the consumption of fruits and vegetables.


http://jncicancerspectrum.oupjournals.org/cgi/content/abstract/jnci;95/18/1404