Fruit and vegetable intake and the risk of overall cancer in Japanese

Re:Fruit and vegetable intake and the risk of overall cancer... by dualogy on Sunday February 05, 2017 @06:51PM (#13575477)

Have always been wondering about the supposed actual mechanism of how any meat would lead to colon cancer more/easier/likelier than fibrous foodstuffs, given that it is fibers that tend to end up in the colon whereas meat tends to be entirely liquefied in the stomach (not just softened and mashed as most plant foods are) and the resulting liquid near-on fully absorbed in the small intestines. Especially as the colon's entire purpose is to hold refuse and foreign substances. So somehow a few drops of leftover meat-liquid micro/macronutrients create more damage than roughage and seeds and such? Curious to hear from the better-informed non-epidemiologists out there ;)

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Re:Fruit and vegetable intake and the risk of overall cancer... by desdiv on Sunday February 05, 2017 @08:01PM (#13575760)

>There are several potential reasons to explain how red and processed meat may cause bowel cancer. Red meat contains a compound which gives it’s red colour, haem, which promotes the formation of potentially carcinogenic N-nitroso compounds. In addition when red meat is cooked at high temperatures, this results in the production of compounds (heterocyclic amines and polycyclic aromatic hydrocarbons) that can cause bowel cancer in people with a genetic predisposition. In addition processed red meat has nitrites, as well as nitrates added to it as preservatives and these are thought to cause cancer. Processing also changes the nature of the meat, which may play a role in its link to cancer.

http://www.wcrf.org/int/blog/articles/2015/10/red-meat-and-b...

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Re:Fruit and vegetable intake and the risk of overall cancer... by dualogy on Sunday February 05, 2017 @08:12PM (#13575801)

Interesting theories! And appropriately cautiously formulated, too.. a lot more to actually investigate then:

> how red and processed meat may cause bowel cancer

> compounds that can cause bowel cancer in people with a genetic predisposition

> nitrites, as well as nitrates and these are thought to cause cancer

> which may play a role in its link to cancer.

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Re:Fruit and vegetable intake and the risk of overall cancer... by TheSpiceIsLife on Sunday February 05, 2017 @08:52PM (#13575967)

Do you know if steamed or boiled meats generate HAs and PAH?

I've know about both for a while and switched to only eating meat I've steamed or boiled.

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Re:Fruit and vegetable intake and the risk of overall cancer... by scythe on Sunday February 05, 2017 @10:54PM (#13576371)

http://cancerpreventionresearch.aacrjournals.org/content/4/2...

>The mechanism is not known, but heme iron has a catalytic effect on (i) the endogenous formation of carcinogenic N-nitroso compounds and (ii) the formation of cytotoxic and genotoxic aldehydes by lipoperoxidation. A review of evidence supporting these hypotheses suggests that both pathways are involved in heme iron toxicity

The irony is, of course, heme iron is the highest bioavailability form of iron, and is one of the main reasons to consume meat in the first place:

http://europepmc.org/abstract/med/3290310

> Food iron is classified as heme or nonheme. Approximately half of the iron in meat, fish, and poultry is heme iron. Depending on an individual's iron stores, 15% to 35% of heme iron is absorbed. Food contains more nonheme iron and, thus, it makes the larger contribution to the body's iron pool despite its lower absorption rate of 2% to 20%.

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Re:Fruit and vegetable intake and the risk of overall cancer... by autokad on Sunday February 05, 2017 @07:51PM (#13575712)

possibly acids making it from the stomach to the colon?

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