I have an incomplete project dating back from a spell working as a research assistant with the Marie Curie Foundation, who at that time had a laboratory in Surrey. It concerns the things we eat and the subsequent development of cancers of the gut and organs associated with the gut. (Oesophagus, stomach, duodenum, pancreas, liver, bowel etc.)
It struck me that if we eat the flesh of our fellow mammals without being very careful about rendering genetic material inactive, we could be inviting trouble from the oncogenes and viruses they might be hosting. Hence my concern that meat needs to be thoroughly cooked to render the protein denatured and hopefully any potentially oncogenic (cancer causing) material inactive.
There is plenty of anecdotal evidence to support such a hypothesis. As examples: Eskimos, who are renowned as eaters of raw meat, have a higher than normal incidence of stomach cancer. Lillian Board, 1948-1970 was a very promising young runner, Olympic silver 1968, European gold 1969, but died of colorectal cancer in 1970. She had been advised to eat raw liver to enhance her running. Was her eating of the liver a contributory cause of her cancer, or purely coincidental?
Epidemiological approach
I submitted the idea to Professor Day in the early days of the European Prospective Investigation into Cancer and Nutrition, EPIC, but that was rather before computers were making such studies possible, and even now I am told it would not be straightforward. I have attached below a copy of my letter to the Professor and his reply.
Experimental approach
More recently, I submitted the idea to Professor Ellis of Queens University Belfast, as I wondered if the kind of experimental approach undertaken by Dr William Crowe, as he and the team studied the link between nitrite-containing frankfurter and colorectal cancer pathology in mice, might supply evidence to support or rubbish such a theory. I appreciate that freeze-drying, though appropriate in the study of nitrites, would denature protein and so inactivate genetic activity.
There are many things that exacerbate cancer pathology. For example, with BBQs, the charring of the outside of the meat is also likely to put us at risk, as is nitrite and as is the deposition of combustion products from the smoke of the fire below.
I long and pray that I may yet be in contact with someone who is in a position to prove or disprove the basic idea.
Footnote
The original letter to Professor Day dated 4th May 1995
Dear Professor Day,
I apologise for troubling you, but, having spoken with Dr Hanson of the participating practice at Elmham, I wondered if EPIC was not exactly the opportunity to prove or disprove a theory that has gnawed at my bones for years!
I worked in a cancer research laboratory for a spell and as a result have an agreement in our own home that the meat we eat is so well cooked as to be as far as possible ‘genetically inactive’.
I do this as I question if we do not put ourselves at risk by eating meat that could contain genetically active material, both viral and animal. So I encourage my family to be very wary of rare meat, typically served when ‘eating out’, and of meat that is difficult to cook evenly or thoroughly, such a sausage or beefburgers and also of the very pleasant and increasingly fashionable eating of partially cooked chops and beefburgers over the BBQ. These latter are often well cooked on the outside and pretty raw on the inside.
The proximity of the freezer and microwave in the modern approach to cooking can also fool us into believing meat is adequately cooked when, deep inside, it is far from it. It is so easy to serve a beautifully browned cottage pie with rich gravy . . . and raw meat. Frozen sausage meat, cooked briefly and fiercely within insulating layers of flaky pastry would also be a good example. When all else is ready, the social pressure to serve the Christmas turkey whe it could have done with several more hours cooking is also well known!
Would it be possible for questions investigating meat cooking and eating habits along this line to be incorporated in a study like Epic. My hunch is that there might be a horrifyingly significant link between our modern, faster and less thorough approach to meat cooking and hence the eating of meat that remains genetically active, and a whole range of viral illnesses and cancers.
Yours sincerely
Professor Day’s Reply
Thank you for your letter regarding meat consumption and cooking methods. Professor Day has asked me to reply to you.
Your theory that the consumption of “undercooked meat” could have a relationship with viral illnesses and cancers would be well worth investigating.
As you may know Epic collects information from a large number of participants in the Epic study. Long with much other information we are collecting a loge amount of detail in relation to all foods consumed both as records of actual and estimates of yearly consumption. We do ask general questions concerning the degree to which meat is usually cooked and should be able to investigate your question at some time in the future.
We would be happy to discuss a formal collaboration with you at some stage in the future, if you would like this.