Certain substances in microwave popcorn packaging that are known as per- and poly-fluoroalkyl substances (PFAS) have associations with cancer.

A 2021 review of previous research says researchers have also found links between PFAS and other conditions, such as impaired thyroid function and infertility.

However, no studies have specifically assessed the effects of eating microwave popcorn, so it is unclear how much difference eating this type of food makes. PFAS are also present in nonstick cookware, some food wrappers, and some stain-resistant clothes and furniture.

Keep reading to find out if microwave popcorn causes cancer.

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Certain chemicals in microwave popcorn packaging have associations with cancer. These chemicals are known as PFAS.

Manufacturers add PFAS to microwave popcorn food packaging because they resist high temperatures, repel oil, and have nonstick properties. These chemicals contain strong bonds between carbon and fluorine atoms, so they do not degrade easily in the environment or in the body. They can leech into water, soil, and food.

No study has assessed the level of PFAS in microwave popcorn specifically, nor their effects on human health. However, according to a 2020 review, previous studies have found that exposure to PFAS has associations with kidney cancer and testicular cancer.

A report by the Centers for Disease Control and Prevention (CDC) identified PFAS in 97% of Americans’ blood. The United States government has implemented laws, regulations, and policies to reduce the use of PFAS.

For people who only eat microwave popcorn occasionally at home, it may not cause lung problems. However, some studies have found a link between PFAS in the blood and the development of asthma in children.

A 2017 study of Faroese children found that PFAS exposure had associations with increased rates of asthma in those who had not received a measles, mumps, and rubella (MMR) vaccine. The same effect did not apply to children who had received the MMR vaccine.

However, a 2019 study on exposure to PFAS before birth in Norway found no increase in asthma cases. More research is necessary to understand the potential connection.

Popcorn lung

People who work around popcorn can inhale large amounts of a chemical known as diacetyl, which some companies add to their popcorn because it mimics the taste of butter. When a person inhales it, diacetyl can cause a rare lung disease known as bronchiolitis obliterans.

In 2000, the National Institute for Occupational Safety and Health (NIOSH) investigated diacetyl exposure at a microwave popcorn plant after a group of former employees developed the condition.

The NIOSH report concluded that the workers likely developed this rare disease from inhaling large amounts of diacetyl. As a result, people sometimes call bronchiolitis obliterans “popcorn lung.”

Since the report, NIOSH has established limits on how much exposure to diacetyl individuals can have through inhalation at work, but these regulations do not cover other types of exposure. For example, some e-cigarettes and vapes may contain diacetyl as flavorings.

There are also other flavorings that have not received as much attention as diacetyl but may also have health risks, including chemicals that mimic butterscotch, caramel, vanilla, and strawberry.

Exposure to diacetyl from making microwave popcorn at home is far lower than the exposure someone would have working in a popcorn manufacturing plant. Therefore, occasionally consuming it may not pose a risk in this setting.

In the United States, the Food and Drug Administration (FDA) currently permits the use of PFAS in microwave popcorn packaging and other greaseproof wrappers for other types of food. This includes convenience food and takeout containers.

Whether this poses a significant risk to health is unclear. The FDA continues to review data on how to use these chemicals safely.

Popcorn manufacturers can also still use diacetyl to flavor products. However, NIOSH recommends controlling exposure to this and other flavorings in workplaces.

Microwave popcorn can be convenient, but there are other methods for making it at home using healthier ingredients. One option is to use a popcorn maker, which can pop kernels using only air and requires no oil.

Another option is the stovetop method, which requires a heavy-bottomed saucepan with a lid. To make 2 quarts, or just under 2 liters of popcorn, a person can use:

  • 2 tablespoons of olive oil
  • 1/2 cup of popcorn kernels
  • toppings to taste

To make the popcorn:

  1. Put the saucepan over a medium heat.
  2. Add the oil and two kernels.
  3. Cover the pot and wait for the kernels to pop.
  4. Take the saucepan off the heat and add the rest of the corn.
  5. Cover with the lid and give the kernels a shake to distribute them evenly.
  6. Let the oil cool for around a minute, then put the saucepan back on a medium heat. Keep the pan moving to cook the kernels evenly.
  7. When the kernels begin popping, open the lid slightly to allow steam to escape, and keep shaking the pan.
  8. When the pops slow down, remove from the heat and put the popcorn into a serving bowl.

People can add many different toppings to homemade popcorn, including salt, pepper, herbs, or spices.

People can eat popcorn every day if they want to. However, if they do eat popcorn regularly, people may want to consider making it themselves.

The following table lists the nutritional information for air-popped popcorn without toppings:

NutrientAmount per cup, or 8 grams (g)
energy31 calories
protein1.03 g
fats0.36 g
carbohydrates6.22 g
of which sugars0.07 g
fiber1.16 g
magnesium11.50 milligrams (mg)
potassium26.30 mg
sodium0.64 mg

Any toppings a person adds will change the nutritional profile.

Other snacks people can add to their rotation include fruits and vegetables, nuts and seeds, and dairy products, such as yogurt, or dairy alternatives. A varied diet can help people obtain their daily recommended nutrients.

While microwave ovens use a type of radiation to heat food, they do not make the food itself radioactive. This means that microwaving food is not likely to cause cancer on its own.

However, similarly to microwave popcorn, convenience foods that come in plastic or greaseproof cardboard may contain PFAS.

Microwave popcorn does not cause cancer in itself, but the packaging that companies use for these products and some other foods can contain PFAS. Research has linked PFAS exposure to cancer.

It is unclear how much of a risk the PFAS in microwave popcorn specifically poses, but people who want peace of mind may wish to make popcorn themselves on the stove or in an air-popping machine.