The study shows that people who frequently eat cured meats may be more likely to develop COPD than people who rarely or never eat such meats.
The researchers included Rui Jiang, MD, DrPH, of Columbia University Medical Center in New York.
They reviewed data on 7,352 U.S. adults who were at least 45 years old (average age: 64).
As part of a larger national health survey, participants took lung function tests and completed dietary surveys.
Using the dietary survey, participants reported how often they ate cured meats, which were defined as bacon, sausage, and luncheon meats not including ham. Cured meat intake ranged from never to more than 14 times per month.
About 1,700 participants said they never ate cured meats. At the other end of the spectrum, about 1,100 participants said they ate cured meats more than 14 times per month.
Lots of Cured Meats, Few Vegetables
The study shows that the odds of having COPD were 78% higher for people who ate cured meats 14 or more times per week than those who never eat cured meats.
People who frequently ate cured meats tended not to eat a lot of fish, fruit, or vegetables. They also were more likely to use tobacco than other participants; smoking makes COPD more likely.
The researchers considered those and other COPD risk factors when analyzing the data.
"Cured meats may contribute to the development of COPD because of their high content of nitrites," which are chemicals added to meat products as a preservative, an antimicrobial agent, and a color fixative, write Jiang and colleagues.
However, Jiang's team didn't test that theory directly. The study doesn't prove that cured meats or nitrites cause COPD.
Though the researchers adjusted for many COPD risk factors, they note that they can't rule out the possibility that other, unmeasured factors affected lung function.
Long-term studies should be done to track COPD and dietary nitrite intake over time, write Jiang and colleagues.
Their report appears in the American Journal of Respiratory and Critical Care Medicine.