The BBC has put out an article talking about the importance of nitrates in the human body, how 80% come from veg and only 5% from meat. However if the article is right, then that 5% from meat causes things like bowel cancer. Whereas the 80% from plants helps fight cardiovascular disease. Much of this all stems from research which won three people the Nobel Prize for discoveries on Nitric oxide.
>> However if the article is right, then that 5% from meat causes things like bowel cancer. Whereas the 80% from plants helps fight cardiovascular disease.
Nitrates are bad for you if they come from meat but good for you if they come from plants? Hmmm. What happens if you eat meat and vegetables together?
>> But Allen adds that nitrites are just one reason processed meats contribute to bowel cancer, and their relative importance is uncertain.
I notice this has gone direct from "there appears to be a weak statistical association between processed food in the diet and bowel cancer" to "processed foods cause bowel cancer".
Cooking meat at 150'C+ absolutely does form carcinogens (nitrosamines). However, processed meats are not usually subjected to such treatment; bacon and sausages are best cooked gently, and ham is typically simmered in hot water. They also have inhibitors such as ascorbic acid added, to prevent nitrosamine formation. The upshot is that nitrosamines are at microgram level in the average serving of bacon, sausage, or ham.
Cooking with "healthy" polyunsaturated vegetable oils also produces carcinogens/toxins (aldehydes, mostly). Our environment is awash with so many carcinogens and toxins - some natural, some manmade - that it's almost impossible to tease out which ones are genuinely causing us harm.
>> “We have observed increased risks associated with nitrate and nitrite from meats for some cancers, but we haven’t observed risks associated with nitrates or nitrites from vegetables – at least in large observational studies where intake is estimated from self-reported questionnaires,”
I despair sometimes, I really do. The problem with the massive upsurge in kids who decide they want to do science, despite having no aptitude for it, is stuff like this.
Given this "paradox", the most likely explanation is that the observed effect has nothing whatsoever to do with the nitrites, but rather with some other variable that you haven't bothered to measure.
>> If you want to eat the right kinds of nitrates and nitrites and avoid the potentially carcinogenic ones
I really, really hope they're not implying that there are two different sorts of NO2-, a bad one and a good one.
Worth pointing out, incidentally, that nitrates are no longer added to processed meats as a preservative, so the only source of dietary nitrates now is (conventionally-grown) vegetables. Nitrites are used to preserve meats because they're more predictable - as noted, nitrates rely on bacterial action for conversion to nitrites. Very little of the nitrite remains by the time you eat it because it tends to gas off as nitric oxide (a tiny amount of the NO also bonds with myoglobin to produce the pink colour).
Thank you for that explanation, I tend to share your view regarding alarmist articles based on somewhat suspect science.
Another ‘observational’ but unscientific comment - my father (born 1922), his mother born 1898), my maternal grandmother born 1892 all lived into their 90’s and except for the last few years of their lives, were generally fit and healthy. They survived war, avoided the very many infectious diseases around at the time - ate bacon, egg, sausage and ham cooked at high temperatures in lard nearly every day of their lives.
I think very carefully about the way my food is produced and what I put in my mouth and really enjoy my bacon, sausages and ham sourced from local farms which use traditional methods to process the meat, I eat a lot less of it than my parents and grandparents, but I really am fed up with this type article which only succeeds in confusing people.
Completely agree about sourcing food from reputable sources (and supporting local businesses who go out of their way to deliver quality produce). Supermarket food quality is appalling, especially meats.
Lard is very safe for cooking precisely because it's stable at high temperatures.
Should have read this before commenting myself, as I was wondering what temperature goes on to constitute a risk of forming nitrosamines. I do wonder whether the same risk exists from frying off celery for soup, or making beetroot burgers. I'll have to reconsider how I cook them.
A popular festive recipe is "pigs on blankets" and so probably more likely cooked at 180degC min. If cooked with other roast veg so possibly even at over 200degC. Whatever most likely over the 150degC you mention.
It's not an on/off thing. Apparently, 150'C the temperature at which you can generate detectable levels. Higher temperatures should produce more. It turns out nobody has completely characterized the chemistry, though.
Bear in mind that:
a) 'detectable levels' is a very small number with modern equipment. As I said, the average sausage might end up with 1-2ug. Is that a problem? Is it more of a problem, than, say, 1-2ug of aflatoxins in your peanuts, or 50ug of pesticide residue on your broccoli? Who knows?
b) an oven temperature of 180'C doesn't mean the meat is 180'C throughout. A roast is usually considered done when the interior is 70'C+ (depending on the meat).
>> are the roasted carrots that were in the oven with them, also a carcinogen now?
Quite. That was my tongue-in-cheek question. Once all this stuff gets into your stomach, how does your body distinguish between those good, healthy nitrates that came from vegetables and the bad ones which ones came from meat ... even though they're chemically identical?
It reminds me of the theory behind homeopathy - that water acquires some sort of 'resonance' from the molecules that were originally dissolved in it, even though none of the original substance remains after dilution. To be clear, I'm not saying something can't be true just because we don't understand it, but if it clearly conflicts with very basic science or logic, there needs to be a pretty robust alternative hypothesis being proposed.
I did read through the link T A T put on and I didn't chock on the bacon sandwiches I was eating when I was reading it.
I found the article quite interesting, and thanks to TheAwfulToad for providing a link that worked, as the one in your post doesn't seem to be working - I'll repeat it here:
That's helpful - I heard they were looking into this. So it seems more important how our nitrates are cooked, although I wonder what temperature is considered a risk? I wonder if celery and beetroot can be an issue if you fry them off for soups etc.
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Meat a threat to our planet. Tonight 9pm BBC 1
Well no XMas meat for me unless...
Corn and shells with veg in sweet chilli sauce 
