Heating Empty Non-Stick Pans: What's The Real Damage?

Heating an empty non-stick pan can be disastrous. Non-stick pans are designed for moderate heat and are not made for high heat. Preheating them for more than 30 seconds or at high settings is not recommended. The pans get too hot too fast, which can damage the non-stick surface, potentially release toxins, and even cause the pan to warp.

Non-stick pans can release toxic fumes if overheated

Non-stick pans are coated with a synthetic chemical called polytetrafluoroethylene (PTFE), commonly known as Teflon. While Teflon itself is considered non-toxic, the coating may begin to break down and release toxic fumes at high temperatures. This typically occurs when the temperature exceeds 500°F (260°C).

The release of toxic fumes from overheated Teflon can lead to a condition known as polymer fume fever, characterised by flu-like symptoms such as chills, fever, headache, and body aches. In rare instances, inhaling these fumes can cause more serious side effects, including lung damage.

Additionally, one of the chemicals released when Teflon breaks down is perfluorooctanoic acid (PFOA), which has been linked to various health conditions, including cancer, thyroid disorders, and developmental problems. While PFOA has been phased out of Teflon production in recent years, it is still possible for PTFE to create PFOA when it breaks down.

To minimise the risk of releasing toxic fumes, it is recommended to avoid preheating an empty non-stick pan. Always add food or liquid to the pan before heating, and avoid cooking on high heat. Proper ventilation in the kitchen is also important, as it helps clear any fumes that may be released.

Pans can warp if heated while empty

The base of your pan cannot expand horizontally beyond the ring, so the only direction it has to go on heat is up or down. More often than not, straight-sided pans will “cup” downward (concave), while slope-sided pans tend to “crown” upward (convex). This has to do with the inclination of crystalline stresses at the “knee” or the curve where the base ascends into the wall.

Thin pans are generally much more likely to warp than thickly constructed ones because the more material there is within its thickness, the more a metal can differentially expand and contract. Types of metal play a big role too, as does their method of manufacture (e.g. stamped pans, owing to stretching at the knee, warp much more readily than spun pans). Given enough use, soft metals (such as copper and aluminium) almost always warp if thinly constructed. Harder, more resistant metals, such as carbon or stainless steel, resist warping but will still do so under the right circumstances.

You can also warp a pot or pan by heating it up too quickly. Even taking a room-temperature pan and heating it up to a high temperature quickly (as opposed to over a longer period of time) causes stress, and the unevenly distributed heat can misshape your metal cookware.

To avoid warping, it's a good idea to let your pan settle down and cool off a little before washing it. Avoid turning the heat on your hob straight to the highest setting. Start on a low heat and turn it up gradually. Ensure the heat is distributed evenly across the whole base of your pan.

Non-stick coatings can deteriorate if exposed to high temperatures

Non-stick pans are designed for moderate heat. They are not made for high heat use, and heating them for more than 30 seconds, or at high settings is not recommended. The pans get too hot too fast, which can damage the non-stick surface, potentially release toxins, and even cause the pan to warp.

Non-stick pans are coated with a chemical compound known as Teflon. This creates a surface that is resistant to sticking, and it can provide the option of using little to no fats, which is desirable for those wishing to limit their exposure to fats or those with certain dietary restrictions. However, when non-stick coatings made with PFAS (per- and polyfluoroalkyl substances) are exposed to temperatures over 500˚F (260˚C), the coating can begin to break down at the molecular level, releasing toxic particles and gases that have been linked to certain cancers.

Empty non-stick pans can reach temperatures of 260˚C in minutes, which can cause the non-stick coating to deteriorate and release toxic fumes. Therefore, it is recommended to put whatever you are cooking into the pan before putting it over the heat, so that some of the heat will be redirected into the food rather than the pan itself.

Preheating non-stick pans for more than 30 seconds is not recommended

Non-stick pans are designed for moderate heat. They have thin sides and bottoms to speed up heating and improve heat distribution. However, this means that they can quickly heat up to temperatures that are too high, causing the non-stick coating to deteriorate and potentially release toxic fumes.

Therefore, it is not recommended to preheat non-stick pans for more than 30 seconds. To heat a non-stick pan safely, set the stove to low to medium heat for a maximum of 30 seconds, just until the pan starts to feel warm. If you are using oil or butter, add it at the beginning and let it heat up with the pan.

If you are using a non-stick pan to boil or simmer liquids, there is no need to preheat the pan at all.

By following these recommendations, you can help ensure that your non-stick pan performs better and lasts longer. Additionally, you can avoid the potential health risks associated with overheating non-stick cookware.

Heating an empty non-stick pan can ruin your food

To avoid ruining your food, it is recommended that you only heat non-stick pans for a maximum of 30 seconds on a low to medium heat setting. You can add oil or butter to the pan at the beginning of this process, which will help you gauge the temperature of the pan—when the oil shimmers or lightly smokes, the pan is ready to cook in. Alternatively, you can add the food to the pan before placing it on the heat, so that some of the heat is absorbed by what you are cooking, rather than just the pan itself.

Frequently asked questions