A Northern Irish food company, Finnebrogue, is offering what it calls “Naked Bacon” – free from chemical preservatives that contain nitrites. But would such bacon actually be more healthful? And what is the deal with nitrites in food?

Sodium nitrite (NaNO2) is a salt containing sodium, one nitrogen, and two oxygen atoms. Nitrate is similar but contains three oxygen atoms (NaNO3). Nitrites are oxidized to nitrates when exposed to the air. Nitrates can also be converted into nitrite in the GI tract. This is why we often talk about the two in food interchangeably.

Sodium nitrite serves a critical function in some foods – it is a good preservative that inhibits the growth of bacteria, specifically C. botulinum, the bacteria that causes botulism. It is therefore incredibly important to food safety, and removing it from meat products could therefore have the unintended consequence of increasing food poisoning.

What are the health effects of consuming sodium nitrite? Much of it is converted into nitric oxide, which is not only harmless, it serves several important roles in the body. One effect is to dilate blood vessels, and therefore can serve to lower blood pressure. In addition:

This effect is associated with a reduced risk regarding cardiovascular disease, myocardial infarction, and stroke. Moreover, dietary nitrate has been associated with beneficial effects in patients with gastric ulcer, renal failure, or metabolic syndrome.

The health concern is that nitrites can also be converted to nitrosamine compounds, which are probably carcinogenic. The amount of nitrites in food converted to nitrosamines is reduced by certain other food substances, such as vitamin C. Therefore, some food manufacturers have been adding vitamin C to food that also contain sodium nitrite.

There is also some evidence that cooking at very high heat can increase the formation of nitrosamines, and so this can also be avoided to minimize this conversion.

It is revealing also to point out what the sources of consumed nitrites/nitrates are. Much of the discussion focuses around sodium nitrite added to meats and other foods as a preservative. However. 80% of the nitrates you will consume in food come from fruits and vegetables. Nitrites are also made in the saliva, which is another significant source.

Contribution from preserved meats is about 10% – depending on your diet, of course. But even the most dedicated meat eater will still get a minority of their nitrites from cured meat.

What about the link between sodium nitrite and cancer? The evidence here is fairly complex and mostly observational. Many studies compare cohorts with the highest and lowest daily meat intake and find mixed results. Some datasets show a slight increase in pancreatic cancer and some GI cancers, but also reduced stomach cancer.

However, more recent research has called these associations into question. The problem with much of the prior research (in addition to being observational) is that it did not control well for many variables. If you look at meat consumption, for example, what aspect of the meat is causing any observed effect, and is it related to other dietary factors that just go along with high meat consumption?

A recent review concludes:

A critical review of the animal toxicology literature of nitrite indicates that in the absence of co-administration of a carcinogenic nitrosamine precursor, there is no evidence for carcinogenesis. Newly published prospective epidemiological cohort studies indicate that there is no association between estimated intake of nitrite and nitrate in the diet and stomach cancer.

So without the nitrosamine, consuming nitrites/nitrates is probably not associated with cancer at all, and has many known health benefits.

What the average consumer can make of all this is a few bottom lines: First, it is still the best advice to eat everything in moderation. The only studies that do show a negative health effect from consuming red or cured meats only finds such results in the highest meat consumption category. So basically, don’t eat a pound of bacon every day (literally, that is what it takes) and you will probably be fine.

Further, nitrites specifically have been unfairly maligned. Their story is much more complex, and overall we should look at nitrites/nitrates as having positive health effects. Remember – they mostly come from fruits and vegetables, and diets high in vegetable nitrates have been shown to be healthful.

Sodium nitrite specifically is an important food preservative, and we should not avoid its use over an unjustified fear.

What about the nitrite-free bacon? This is a good example of how food fears based on outdated, preliminary, or incomplete information can lead to bad eating decisions. First, many products touting themselves as not using added sodium nitrite, or avoiding chemical preservatives, actually do contain nitrites. The makers of Naked Bacon, for example, claim:

Finnebrogue said it worked with a Spanish chemist to develop the new flavouring from natural Mediterranean fruit and spice extracts and apply it to British bacon for the first time.

I wonder if those fruit and spice extracts contain sodium nitrite? That is often the case with similar products – they use the “appeal to nature” fallacy to imply their products are better because they use only natural ingredients. The source of the sodium nitrite, however, has zero effect on its health effects.

But thinking that your bacon is healthier may lead to consuming more fat and calories. This is the fallacy of blaming specific ingredients or types of food for being “bad” and thinking that avoiding them will make your diet magically healthy. Companies are quick to exploit this, with, for example “low fat” products that are loaded with sugar. Such products are often sold as “guilt free” but this is a scam.

Again – just eat a variety of foods in moderation, make sure you get enough fruits and vegetables, and watch your total caloric intake. Don’t be lulled into a false sense of security by thinking you are eating a “superfood” or “guilt-free” food.