Does Processed Meat Affect Our Lung Function? 

If the nitrites in foods like ham and bacon cause lung damage, what about “uncured” meat with “no nitrites added”?

“Recently, the World Health Organization (WHO) classified processed meat as carcinogenic to humans.” Also known as cured meat, such as bacon, ham, hot dogs, lunch meat, and sausage, processed meat is definitively cancer-causing. What’s more, “high processed meat consumption has also been associated with increased risk of all-cause mortality”—that is, dying prematurely from all causes put together—“and is a risk factor for several major chronic diseases, such as type 2 diabetes, coronary heart disease, and stroke.” What about lung issues like asthma?

As I discuss in my video Does Processed Meat Affect Our Lung Function?, nitrites are added to processed meats as preservatives to preserve their pink hue (so the meat products don’t turn gray), keep them less rancid-tasting, and prevent the growth of diseases like botulism. But, if that same sodium nitrite is put into the drinking water of lab animals, they develop emphysema. Nearly all of them develop emphysema. That was the extent of the scientific knowledge we had on the subject going into 2007, then this study was published: “Cured Meat Consumption, Lung Function, and Chronic Obstructive Pulmonary Disease Among United States Adults.” It found that frequent consumption of cured meat is associated with an increased risk of people developing diseases like emphysema, a form of chronic obstructive pulmonary disease (COPD). As you can see below and at 1:32 in my video, eating it every other day appeared to triple the odds of severe COPD. 

Since it was a snapshot-in-time study, we don’t know which came first, the sausage or the COPD. For that, we need prospective studies that follow people over time, and the big twin Harvard studies in women and men both found that “the risk of newly diagnosed COPD increased with a greater consumption of cured meats after adjustment for many important confounders.” 

We now have studies involving hundreds of thousands of people showing that higher consumption of processed meat is associated with a 40 percent increased risk of COPD. It comes out to about an 8 percent higher risk of COPD for each hot dog eaten in a week or each weekly breakfast link sausage. What is going on?

Yes, there are advanced glycation end-products (AGEs), so-called glycotoxins that “occur naturally in meat and are formed through heat processing,” that may be pro-inflammatory, as well as saturated fat that can also trigger inflammation in the airways. And there’s the high salt content that can present a potential risk for lung inflammation, and the suggestion that processed meat intake may increase systemic inflammation in general. However, the reason attention has focused on the nitrites is because nitrites themselves may be “one of the mechanisms by which tobacco smoke causes COPD” and other diseases like emphysema. “Cured meats are the principal source of dietary nitrites,” but “nitrites are also byproducts of tobacco smoke.” One of the main constituents in cigarettes, besides carbon monoxide and nicotine, are nitrogen oxides that are converted in the lungs to nitrites.

The way nitrites appear to cause lung damage is by affecting connective tissue proteins like collagen and elastin, which are what help keep the airspaces in our lungs open. But nitrite can modify these proteins in ways that “mimic age-related damage, including elastin fragmentation.”

With that much lung injury, it’s logical to assume that processed meat consumption could also exacerbate the disease of those who already have it. And, indeed, cured meat consumption increases the risk of people with COPD ending back in the hospital; those eating more cured meat on average have about twice the risk of readmission. It appears the more you eat, the worse it is, as seen here and at 3:56 in my video.

“Regarding lung health, processed meat intake has been associated with a likely increased risk of lung cancer, decline in lung function and chronic obstructive pulmonary diseases (COPD),” but what about asthma? High consumption of processed meat has also been “associated with higher asthma symptoms.” 

We know that “higher maternal intake of meat before pregnancy may increase the risk of wheezing” in her children later on, based on a study of more than a thousand mother-child pairs. (And we aren’t talking about aspirating meat into our lungs and getting misdiagnosed with asthma.) In fact, “those who ate the most cured meats were 76% more likely to experience worsening asthma than those who ate the least.” Since obesity is a likely risk factor for asthma, might meat’s influence be indirect, by contributing to weight gain? That may be a small part of it, but the main effect appears to be direct, “suggesting a deleterious role of cured meat independent of BMI,” body mass index, a weight measurement. Put all the studies together, and “processed meat intake appears to be an important target for primary prevention of adult asthma.”

Even if you don’t have any lung issues, processed meat consumption was negatively associated with measures of normal lung function, while fruit and vegetable consumption and dietary total antioxidant capacity were associated with better lung function.

Can we just eat all-natural, uncured hot dogs, with “NO NITRATES OR NITRITES ADDED,” like these see here and at 5:35 in my video? 

If you use a magnifying glass and peer at the small print, it says “except those naturally occurring in sea salt and cultured celery juice.”

See, to avoid saying “added nitrites,” food manufacturers may add something that has a lot of nitrates, like celery, and also bacteria, “a starter culture to convert the nitrate to nitrite.” So, nitrites are being added and consumers are being duped.

The European Union doesn’t allow this kind of consumer fraud and “considers the use of plant extracts containing high levels of nitrate with an intended technological purpose of preservation to be a deliberate use of a food additive,” and manufacturers must explicitly label their products as “containing nitrate or nitrite.” You can’t even call it natural. “In the European Union, ‘natural’ claims are also not permitted….”

When Consumer Reports put it to the test, it found the nitrite levels in all the products were essentially the same, so “‘no nitrites’ doesn’t mean no nitrites.” Consumer Reports and the Center for Science in the Public Interest have petitioned the U.S. Food Safety and Inspection Service of the Department of Agriculture to stop this misleading practice. Nitrites are nitrites, and “their chemical composition is absolutely the same, and so are the health effects.”

Yes, processed meat is a known carcinogen, but How Much Cancer Does Lunch Meat Cause? 

I have many videos on both nitrites and nitrates. I know it can be confusing, so be sure to check them out.