Im a crossfitter, obviously, and by instinct and belief i tend to eat according to Zone and Paleo principles. However, its important that we are aware of evidence linking certain types of food to Colorectal cancer

All professionals should be aware of the recent reports and research carried out by  the "world Cancer Research Fund International"  especially theri word that links diet with certain types of Cancer.

 It is very common to promote limited anecdotal  small scale clinical evidence  as fact: it should not be ignored: but a knowledge of hard science is also useful, as is the ability to see limited and skewed research. But, check out  The World Cancer Reports here

 

I think its important to understand that  there is  a substantial issue of genetic predisposition.

Red meat and Cancer?

There are several potential underlying mechanisms for a positive association of red meat consumption with colorectal cancer. Red meat contains haem, which promotes the formation of potentially carcinogenic N-nitroso compounds as well as cytotoxic alkenals forms from fat peroxidation. Red meat cooked at high temperatures, results in the production of heterocyclic amines and polycyclic aromatic hydrocarbons that can cause colon cancer in people with a genetic predisposition 

A substantial amount of data from cohort studies showed a dose-response relationship, supported by evidence for plausible mechanisms operating in humans. Apparently  red meat is a convincing cause of colorectal cancer.

 

Processed meat 

There are several potential underlying mechanisms for a positive association of red meat consumption with colorectal cancer. Red meat contains haem, which promotes the formation of potentially carcinogenic N-nitroso compounds as well as cytotoxic alkenals formed from fat peroxidation. The formation of N-nitroso compounds is particularly important when nitrate or nitrite is added as a preservative. Red meat cooked at high temperatures, results in the production of heterocyclic amines and polycyclic aromatic hydrocarbons that can cause colon cancer in people with a genetic predisposition

They conclude that processed meat is a convincing cause of colorectal cancer. 

 

Fish ( and OMEGA 3 supplamentation)

It is biologically plausible that long-chain n-3 polyunsaturated fatty acids (PUFAs) found in fish protect against cancer . Fish oils reduce tumours in animal studies.  Likely mechanisms are thought to include their role in reduction of n-6 PUFA-derived eicosanoid biosynthesis (eicosanoids influence inflammation) and direct inhibition of cyclo-oxygenase-2, also implicated in the cancer process.

This mechanism, though plausible, is not well supported.

Alternative suggestions include the relatively high selenium or vitamin D content of fish.  The  Panel considered that there was limited evidence suggesting that fish protects against colorectal cancer. The CUP Panel agreed that the updated evidence showed inconsistency and was too limited to draw a conclusion.

 

Hmm, I will have to do a lot of work on this?