Meat doubles bowel cancer risk in one in three people

Given that we have the highest rates of bowel cancer in the world, this seems like something we should be paying attention to.

Facts:

  • NZ women have the highest rates of bowel cancer in the world
  • The highest bowel cancer rates are in New Zealand, and in Europe, they are in Hungary, the Czech Republic and Slovakia - all on a meat-heavy, low-fibre, sugar-rich, highly processed diet
  • The lowest bowel cancer rates are in Japan, Loma Linda and Okinawa – all on a healthy, balanced, plant-based, high-fibre, wholefood diet
  • Colorectal cancer is the third leading cause of cancer death in both men and women across most racial groups
  • World Health Organisation states that “Bowel cancer is 3% genetic”

Colorectal cancer is a disease that is strongly influenced by certain types of diets.  It happens in one in three individuals; that these individuals are actually at even at higher risk of the carcinogenic effects in processed meat.  It’s anything that is cured, dried, smoked, cooked or packaged.  And so the most common items around the countries we were studying would include bacon, ham, hot dogs, sausages, pate and cold cuts.  It is conceivable that selected individuals at higher risk of colorectal cancer based on genomic profiling could be targeted for screening, diet modification and other prevention strategies.  I think that we should also limit our consumption of processed meat.  People with the genetic variant have an even higher increased risk of colorectal cancer if they consume high levels of processed meat, but the baseline risk associated with meat is already pretty bad.  Diet is a modifiable risk factor for colorectal cancer”  
Study author, Dr Jane Figueiredo, Ph.D., Assistant Professor of Preventive Medicine at the Keck School of Medicine, University of Southern California, April 2014.

Many studies have shown that “eating too much meat is bad for your health” but this new study hits the same conclusion from a completely different perspective.

This first ‘large-scale genome-wide analysis of genetic variants and dietary patterns’ research has found that just “eating five or more servings per week of processed meat more than doubles the risk of colorectal cancer in people who have certain variants of a specific gene.  The startling thing is that around one in three of us have this gene, and that most of us eat far more meat than this amount daily. 

We’ve all heard reports about how certain foods may lower or raise the risk for certain diseases, such as cancer.  But how our personal genetic variations modify the effects of diet on disease has not yet been thoroughly investigated.  Our results, if replicated by other studies, may provide us with a greater understanding of the biology into colorectal carcinogenesis”
Dr Ulrike Peters, Ph.D., M.P.H, of the Fred Hutchinson Cancer Research Center’s Public Health Sciences Division, April 2014.

The risk of colorectal cancer associated with processed meat was significantly higher among people with the genetic variant rs4143094 (about 36% of the population).

The transcription factor encoded by this gene plays a role in the human immune system.  The researchers suggest that digestion of processed meat may promote an unhealthy or damaging immunological/inflammatory response that may trigger cancer tumor development.

Another statistically significant diet-gene interaction was found in variant rs1269486.

For people with this variant, eating your fruits and veggies ensures even greater protection against colorectal cancer risk.

“The possibility that genetic variants may modify an individual’s risk for disease based on diet has not been thoroughly investigated but represents an important new insight into disease development.  The study is the first colorectal cancer investigation with the statistical power to identify gene-dietary interactions across the genome of a large population of individuals
Researcher Li Hsu, of the Fred Hutchinson Cancer Centre in Seattle, April 2014.

Looking at this again; more than one in three people carry the gene that significantly raises the risk of developing bowel cancer, by eating processed meat.  Many people also carry the gene that protects you against bowel cancer (triggered by a diet high in fruits and vegetables – typically a plant-based wholefood diet).

So over 30% of the population are at risk for one of the most widely spread and dangerous cancers, that is mostly preventable, that is killing us in the thousands, and can be mitigated by simple and easy to achieve daily dietary changes?

Study by Dr Jane Figueiredo of the University of Southern California’s Keck School of Medicine, as published in the April 18 issue of the journal PLoS Genetics.  The study was originally presented to the annual American Society of Human Genetics 2013 meeting, the largest gathering of human geneticists in the world, on October 24, 2013.  The research was a meta-analysis of 10 different observational studies involving 18,000 people across the United States, Canada, Australia and Europe.  They studied blood samples of 9,287 people with colorectal cancer to 9,117 people without the disease, looking through 2.7 million genetic variants, identifying those that are associated with the effects of meat, fibre, fruit and vegetable consumption.  This very large study was sponsored by the National Institutes of Health-funded Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO) and Colorectal Cancer Family Registry.  As reported by The Sydney Morning Herald, Science Codex and voanews.com on April 17 & 18, 2014.


 

Posted: Sunday 4 May 2014