Nitrates, nitrosamines and cancer

[Butterbean]

Here is something I thought might be useful and I think it compliments Reddals post about nitrate levels after curing.

Putting things in perspective

If you are reading this you are familiar with cured meats and I`m sure you are also familiar with the concern many have with the use of nitrates and the alleged danger associated with them. It seems nearly everyone has heard how nitrates are bad and how bacon causes cancer. No one wants cancer. It`s a scary disease. This concern seems common and can even be seen among meat processers where in some circles more effort seems to be devoted to trying to figure the correct amount of cure than how to make quality products. However, the meat community is generally more knowledgeable than the general public and understand nitrate is not the problem because nitrates are found everywhere and are the foundation to the nitrogen cycle which is one of the key elements of life on this planet. With our knowledge we understand that it is not the nitrate itself but the nitrosamines that is the problem and we usually leave it at that without asking more.

My son is a cardio thoracic surgeon and we have discussed the topic of nitrates on many occasions and he says the idea that nitrosamines cause cancer isn`t exactly true. He explained that cancer is caused by a genetic anomaly which some people are predisposed to while others are not. He says this anomaly is triggered by what we call carcinogens. Ok, using simple logic we can deduce that nitrosamines are carcinogens so by definition they do cause cancer so eating bacon preserved with nitrite can cause cancer? He says, not exactly, because the problem with this argument is the world is full of carcinogens so you can`t just blame cancer on bacon.

So what is a carcinogen? The list is long and includes sunlight, mineral oil, balloons, condoms, latex, wood dust, beer, whiskey and a host of other things including drinking water. Carcinogens are found everywhere but the one we hear the most about in our craft is nitrosamine so what`s the deal with that?

Simply put a nitrosamine is a molecule that is formed when a protein bonds with an amine. Its formation can only occur under certain conditions, including strongly acidic conditions such as those found in the human stomach or heat. High temperatures, as in frying, can enhance the formation of nitrosamines.

Though there are several types of nitrosamines the one we concern ourselves the most with is NDMA which appears to be the most volatile. When we think of this, we equate its occurrence with bacon and I think we all would agree that bacon has gotten a pretty bad reputation. But is this reputation justified? Maybe, maybe not. In years past meat processors used nitrates in excess to speed the curing time for products but once researchers understood the mechanics of nitrates guidelines were put in place to prevent their excessive use so in a way history is haunting us and this is not so true today. It`s important for one to keep in mind that as soon as nitrite is added to meat it reacts and begins to break down. Cure 1 is called a quick cure for this very reason and when the guidelines are followed there is little nitrite left in the finished product. To try and get my head around this discussion with my son I did some digging on my own and found some interesting information I thought I`d share.

In 1987 a random sample of bacon was purchased in the Washington DC area and it was determined the average amount of nitrosamine (NDMA) in the fried bacon was 0.3 ppm. To put this in perspective, it`s interesting to note that the EPA considers safe drinking water to contain no more than 10 ppm of nitrosamine.

So if nitrosamines can be found in bacon and drinking water but where else can it be found? Apparently they are everywhere and not just in bacon but here is some data from various foods and their nitrosamine contents I thought interesting. Numbers are in ppm.

Tinned Fish 0.05 - 33.00
Tinned Meat 0.30 - 2.70
Tinned Offals 0.10 - 3.14
Tinned Food 0.10 - 33.00 (canned green beans and such)
Whisky 1.87
Fresh vegetables <3.3
Fruit 0 - 6.21
Beverage 0 -3.57
Beer 0.5-1.87

And cooked bacon was 0.3 ppm? Wouldn`t it appear that it would be better to lay off the tuna and the canned green beans and ask for a hundred more pieces of bacon?

What`s also interesting is research has shown the addition of different spices such as pepper, paprika, mushrooms, cucumber, vegetables, etc. could deliver chemical precursors of N-nitrosamines. Are we to stop using these? Also, raw salts, such as sea salt, can do the same via the introduction of their chemical impurities such as nitrates. When curing meat using sea salt, have you ever heard of anyone account for the natural nitrate in their sea salt? I haven`t. The use of sea salt in bacon is fairly common. Should they stop?

Nitrosamines can also be found in all cooking oils and range from 1-10 ppm depending on the oil. And fried bacon only averages 0.3 ppm yet I think we all can agree that bacon is the poster child for unsafe cancer causing foods.

My mind can`t help but think of that delicious Chinese stir fry where the scorching hot wok is dosed with oil and filled with nitrate laden vegetables along with meats. I can`t help but think this would be a nitrosamine factory of sorts. Should we stop eating Chinese food? So, why pick on bacon?

Quoting the American University, "the process of cooking these types of food (bacon or a cheeseburger) can lead to the formation of cancer-causing compounds. Frying bacon and searing a hamburger or steak are both processes that develop tasty flavors alongside compounds that are known carcinogens, and while these molecules can cause cancer, the relative risk that we expose ourselves to by eating them is relatively small."

Of course, to be balanced, there is another school of thought like the Physicians Committee for Responsible Medicine who feel we should not consume any of these foods. They claim the worst foods are grilled chicken, steak, hamburger, BBQ`ed pork and grilled salmon. Instead, they suggest healthy alternatives like BBQ Style Tofu, Missing Egg Sandwich and Vegetarian Reuben Sandwiches which I am sure are all to die for. Incidentally, they also accept donations for their cause and sell vegetarian magazines for hospital waiting rooms so they can educate the public on the hazards of eating meat.

While I don`t intend to downplay the horrors of cancer I do think it important to put things in perspective because if you look at the things that contain carcinogens I don`t see how we can avoid them and think bacon has been treated unfairly. Of course if your body doesn`t have the genetic predisposition to contract cancer then you have nothing to worry about anyway. Sadly, if you do, your carcinogen may come from the pickle you ate or the water you drank and possibly even the bacon you had for breakfast so yes, I guess in that respect - bacon can cause cancer. However, while the researchers may be undecided on the exact source of the carcinogen that triggered your cancer they all will agree that botulism kills and the use of nitrates is the only feasible tool we have at our disposal to prevent this from happening.

As mentioned, my son is a cardiothoracic surgeon and has recommended a diet to his mother to lower her cholesterol and some other things I don`t quite understand. Though she has always eaten "healthy" by today`s standards she was going to have to start taking medicine if the numbers didn`t improve. One of the main foods in her new diet is bacon and generous portions of it. After two weeks and many slices of bacon later her cholesterol dropped fifty points without the use of any medications and her other numbers which I don`t understand also improved. I don`t profess to understand much of this nor do I understand half of what my son explained to me but one thing I do know is he loves his mother, knows his medicine and has a better understanding of meat processing than the average doctor. I also find it refreshing to learn that bacon or cured meats aren`t the villains some would have us to believe - not that it would have ever swayed my love of these foods - but it is nice to know its not bad as some would have us believe.

My son had a lot more to say about all this than this but you get the gist.

[reddal]

Thanks for all the info.

Browsing the internet, there is so much scaremongering and misinformation about nitrates/nitrites in cured meat. Vegetables have vastly more eg :

Nitrate/nitrite levels
Cured Meats : less than 5ppm (based on the lab test I did)
Lettuce : 792ppm link - Table 2.5
Spinach : 2170ppm link - Table 2.5
Celery : 1102ppm Table 2

I've seen a couple of people claim that despite the fact there is vastly more nitrates in vegetables than cured meat - the nitrates in cured meat are the problem because when they occur in vegetables they tend to be with Vitamin C, eg from here:

If it's natural in some foods, it can't be all that bad, right? Well, this is true in some cases. Those fruits, vegetables and grains that are naturally rich in nitrates can actually provide many health benefits, in particular the relaxation of blood vessels and improved blood flow. In fact, it's important that our bodies actually produce nitrites. Regardless, the way that these naturally occurring nitrates are not harmful to you is because the vitamin C in fruits and vegetables naturally prevents nitrosamines from forming, and this is one reason that it's better to eat fruits and vegetables than cured meats.

I don't believe this argument at all. However its part of the reason I'm now adding vitamin C to my cured meat product - partly as an extra safety hurdly to ensure the curing process works well, and partly in order to have a response to those that make the point above.

- reddal

[Butterbean]

I agree, there is way to much scaremongering and much of this is agenda driven usually for financial reasons.

My son says nitrates are nitrates no matter their source and the human body only sees things on molecular levels so the idea that "organic" nitrates are somehow better for you is rubbish.

He also talked a good bit about how the naysayer research was conducted but I can't relay this with any clarity other than to say it was questionable at best. Bottom line is cancer is an extremely complicated disease with a lot of variables.

Personally, I've always thought it amazing how mankind ever figured out how to use the nitrogen cycle to cure food and make it safe. We are after all working in tandem with nature when we preserve food when we use nitrates. In my mind, this is beautiful and what could be more natural than this? Its funny though how once mankind learned nature's mechanics and and called it science this "magic" then becomes tainted and viewed as unnatural.

I also found an interesting study regarding the use of "organic" nitrates where "nitrate-free" bacon (cured with celery juice powder) was tested and found to contain ten times the allowable nitrate levels but due to regulatory semantics its perfectly legal to sell these products yet you'd have to bin it had it been made using our curing agents. This in itself tells me nitrates aren't as dangerous as some would have us believe.

Myself, I choose to use common sense and follow the guidelines and try and educate people the best I can though I know this will be a difficult task.

[bcuda]

Thank you for giving all of us a better understanding of nitrates. It makes me feel a lot better for sure!