If you're a fan of microwave popcorn but have heard that eating it regularly -- or even occasionally -- increases your risk of lung cancer, you may be understandably concerned. While there is some evidence that certain chemicals used in production of microwave popcorn may be harmful, there's no direct link to lung cancer.
Risk of Cancer
The rumor that microwave popcorn increases your risk of lung cancer is an amalgamation of two separate issues: microwave popcorn may contain chemicals that can increase cancer risk and chemicals that can increase the risk of lung disease. The cancer risk comes from perfluorooctanoic acid, a chemical produced by a compound used in the nonstick coating on popcorn bags. It's been associated with increased risk of prostate cancer in factory workers, Dr. Frank Gilliland and colleagues note in a 1993 article in the "Journal of Occupational and Environmental Medicine."
Lung Disease
A second chemical used in the production of microwave popcorn, diacetyl, increases the risk of lung disease, Dr. Frits van Rooy and colleagues explain in a 2007 article in "Respiratory and Critical Care Medicine." Diacetyl is an ingredient in popcorn flavoring, and factory workers regularly exposed to it in large quantities have increased risk of developing bronchiolitis obliterans, which is a scarring of the small airways in the lungs due to exposure to irritating chemicals or particulate matter. It makes it difficult to breathe and can cause death.
Eating Microwave Popcorn
You probably aren't at significant health risk from microwave popcorn even if you eat it fairly regularly. This is because the studies that have linked chemicals in the popcorn to negative health outcomes are based upon factory workers, who are exposed to perfluorooctanoic acid and diacetyl in very large quantities, on a regular basis, over a long period of time. You're exposed to much smaller quantities on a more occasional basis when you eat popcorn.
Mitigating Risk
If you are a fan of microwave popcorn and want to continue to eat it but are worried about exposure to chemicals, you might consider consuming it only occasionally -- you can handle exposure to potentially harmful chemicals better if you are exposed infrequently. Also, diacetyl, which you'd be exposed to in larger quantities than perfluorooctanoic acid, has a boiling point slightly less than that of water, meaning you'll breathe less of it if you let your popcorn cool before you open it.
References
- "Journal of Occupational and Environmental Medicine"; Mortality Among Employees of a Perfluorooctanoic Acid Production Plant; Frank Gilliland et al; September 1993
- "Respiratory and Critical Care Medicine"; Bronchiolitis Obliterans Syndrome in Chemical Workers Producing Diacetyl for Food Flavorings; Frits van Rooy et al; May 2007
- National Jewish Health: Bronchiolitis Obliterans
