Do non-stick pans work? Are they safe?

Find out why food sticks to pans and whether the coveted non-stick pan is actually safe.

If you cook regularly, you’ve probably felt the uncontrollable desire to have a pan that doesn’t stick (or promises not to stick at all). But why does food stick to heated surfaces, even when using oil and non-stick pans? And, after all, are pans that don’t stick safe? Check it out!

Why does food stick to pans?

Despite the use of non-stick pans , food sometimes sticks to a heated surface, even if oil is used. The experience is often frustrating, and many people even accuse brands of false advertising. But science explains why this happens.

Researchers at the Czech Academy of Sciences have begun investigating the fluid properties of oil on a flat surface, such as a frying pan. Their work, reported in the journal Physics of Fluids, shows that convection may be to blame for food sticking to the bottom of a pan .

The experimental investigation used a set of non-stick pans with a surface composed of ceramic particles. A video camera was placed above the pan while it was being heated. It was used to measure the speed at which a dry spot formed and grew. Other experiments, which used a Teflon -coated pan , showed the same result.

Result

According to the researchers, when the pan is heated from below, a temperature gradient is established across the oil film. For common liquids, such as the sunflower oil used in the experiment, the surface tension decreases as the temperature increases.

A surface tension gradient is established, directed away from the center where the temperature is highest and toward the edge of the pan . This gradient sets up a type of convection known as thermocapillary convection, which moves the oil outward. When the oil film in the middle becomes thinner than a critical value, the film ruptures.

To prevent food from sticking to the pan , you can increase the thickness of the oil film. Or use moderate heat, completely wetting the surface of the pan with oil. Or use a pan with a thick bottom or stir the food regularly during cooking.

The phenomenon also occurs in other situations, such as in thin liquid films used in fluid distillation columns or other devices that may have electronic components.

Are non-stick pans safe?

Spending the morning at the kitchen sink scraping off the charred remains of last night’s dinner can be the most boring chore in the world! That’s why non-stick pans and frying pans may seem like attractive alternatives while you’re washing dishes. But what about safety?

Teflon cookware is the most popular type of nonstick cookware. The material, known as polytetrafluoroethylene (PTFE), is a clear plastic used to coat metal pots and pans . The plastic provides a waxy surface that is easy to clean.

Experts tend to agree that Teflon itself isn’t a problem. The coating itself is considered nontoxic. Even if you ingest small flakes, they’ll pass right through you. But some experts are concerned about what happens when Teflon is heated too much, because the coating starts to disintegrate.

As Teflon decomposes, it releases a series of toxic gases. Inhaling these chemicals can lead to polymer fume fever, also known as Teflon fever. This condition is characterized by flu-like symptoms such as chills, fever, headache, and body aches. 

It usually occurs after four to ten hours of exposure to Teflon fumes and can last up to 48 hours. However, some studies also show that it can pose other, more severe health risks, such as lung damage.

The FDA , a federal agency within the U.S. Department of Health and Human Services, says Teflon cookware is safe. However, many studies have looked at the health effects of Teflon’s chemical byproducts, such as PFOA.

The use of PFOA

The use of Teflon raises some concerns, mainly due to one of its components — perfluorooctanoic acid (PFOA).

PFOA has been linked to a number of health problems in laboratory animals, including increased liver, pancreas, and testicular tumors and reduced fertility. It was initially believed that the chemical was burned off during the Teflon manufacturing process. However, experts have since found traces of the acid in these materials. 

Furthermore, a study conducted in the United States between 1999 and 2000 found that 98% of participants had traces of the chemical in their blood. Following this discovery, the EPA ( United States Environmental Protection Agency ) is pushing for the elimination of PFOA from Teflon products.

Environmental exposure

Much of the data on these toxins comes from environmental exposures, such as drinking water or factory settings. In these situations, exposure levels are much higher than they would be in non-stick pans. Therefore, it is likely that the pan you have at home is not actually dangerous. After all, the temperatures at which food is prepared are not as high.

On the other hand, research suggests that pans can easily reach a temperature hot enough to disintegrate Teflon. In 2001, a group of researchers in Canada published a study in the journal Nature . In it, they revealed that Teflon is capable of disintegrating at 360 degrees Celsius.

A Teflon-coated pan can reach 399 degrees if left on a stovetop for eight minutes at high temperatures, according to a 2017 article published in the journal Environmental Science and Pollution Research . 

At lower temperatures, the Teflon coating still breaks down over time, according to one study . If you consistently heat your pan to 260 degrees, your nonstick pan should last about 2.3 years. So it’s best to limit its use.

Microplastics 

Non-stick pans are also believed to pose environmental risks. According to a 2022 study , just a small crack in the surface of a non-stick pan can release more than 9,000 microplastic particles.

A broken coating can cause even more damage. Experts have found that when simulating a pan with a broken coating, a cooking process lasting just 30 seconds can release up to 2.3 million tiny particles during the preparation of a meal — especially when the pan interacts with other materials, such as stainless steel, plastic and wood.

Microplastics are categorized as plastic particles whose diameter is less than 5 millimeters. And, in addition to posing health risks when consumed, they can also cause numerous environmental impacts, and part of this is due to the size of these particles. 

As suggested by their name and categorization, microplastics are relatively small, which makes them difficult to remove from the environment and possibly easier to introduce into the human body. Microplastic pollution, for example, is already widespread throughout the world. Microplastics are the main pollutant in the oceans and have been found in the most remote corners of the Earth, including Mount Everest. 

Scientific evidence also shows that these microplastics can contribute to a range of negative health impacts, including heart, lung, developmental, reproductive and cancer problems. 

Furthermore, Teflon belongs to the group of eternal chemicals, which means that it is prevalent in the environment and in the human body. When broken, the coating can end up contaminating bodies of water during cleaning and can also be ingested by humans. 

How to minimize the risk of contamination 

By following some tips, you can minimize the risk of Teflon contamination, whether through ingestion or proximity to the material’s vapor. Check it out: 

• Do not preheat empty Teflon pans — the heat can promote the release of polymer vapors; 
• Cook at low or medium temperatures; 
• Use plastic, silicone or wooden utensils, as metal utensils cause wear to the material; 
• Replace old pans if you notice scratches or other damage. 

However, it is important to note that in most cases, it is recommended to discard these pans and other non-stick devices that contain Teflon. However, if you still want that famous pan that does not stick , there are other options that have less impact on the environment and health. 

Cooking, in general, is a method of promoting health by distancing yourself from frozen or ultra-processed foods that do not require cooking. So, how about extending these benefits to the pan you use? 

Non-stick pan: which is the best?

As mentioned, in some cases, it’s best to ditch Teflon pans altogether, especially if you’re pregnant, breastfeeding, or have young children. PFOA, in particular, has been linked to developmental issues in children. That’s because the chemical is considered an endocrine disruptor, meaning it interferes with the body’s hormone system.

Additionally, PFOA exposure causes elevated estrogen in male rats and delayed mammary gland development in female mice, a study found . In humans, the chemical is associated with obesity , diabetes , poor sperm quality , and irregular menstrual cycles .

If you are one of those people who dream of having a pan that does not stick , opt for those made of anodized aluminum . The product that protects against corrosion and scratches can provide the best cost-benefit. 

Ceramic is also non-stick and safe, as it does not release residue. If well maintained, a cast iron pan can also serve as another non-toxic and non-stick pan. In addition to enriching food with iron.