Quick Facts

• Dirty air fryers emit 23% more volatile organic compounds and twice as many ultrafine particles compared to clean units
• Air fryers still produce 10-100 times fewer emissions than deep-fat frying methods
• Regular thorough cleaning eliminates the increased health risks from residue buildup

Air fryers may be working against your health if you’re not cleaning them properly, according to new research from the University of Birmingham.

The study tested an air fryer used more than 70 times and found it released 23% more volatile organic compounds (VOCs) and 236% more ultrafine particles compared to a clean unit. Oil residue and food particles accumulated in hard-to-reach spots inside the appliance, then got re-cooked during use.

“Oil residue and food particles build up in hard-to-reach spots inside the appliance. When you heat up the fryer again, those remnants essentially get re-cooked, releasing compounds into your kitchen air,” the researchers explained.

The study used custom air quality chambers to measure emissions during cooking. Researchers found pollutant levels varied by food type, with total cooking VOCs ranging from 17.8 to 184.0 micrograms per minute.

Dr. Brian Helfand, a urologic oncologist at Endeavor Health, warns about long-term exposure risks. “These compounds have been linked in laboratory studies to DNA damage and increased cancer risk with long-term, high exposure,” he said.

Despite the cleaning concerns, air fryers remain significantly healthier than traditional frying methods. The Birmingham study confirmed air fryers produce only a fraction of emissions compared to shallow or deep-fat frying.

“The results confirmed that while foods with high fat content do produce more emissions in the air fryer, they produce only a fraction of what we see in cooking methods such as shallow or deep-fat frying,” said lead researcher Ruijie Tang.

Professor Christian Pfrang, senior author of the study, emphasized the solution is straightforward. “Our study shows that repeated use of air fryers without being able to clean the more inaccessible cooking surfaces can negate some of the benefits for indoor air quality,” he said.

The research suggests manufacturers may need to redesign air fryers for better cleanability. Current models have areas that are difficult to reach during routine cleaning, allowing residue to accumulate over time.

Health experts also caution against the “health halo” effect with air fryers. Dr. Manan Vora warns this false sense of security can lead to larger portions and more frequent consumption of processed foods.

“Just because something is cooked that way, it isn’t necessarily healthy,” said Megan Wroe, a registered dietitian at Providence St. Jude Medical Center. “Specialty recipes like air-fried Oreos are still not a healthy choice, even if they are technically healthier than a deep fried Oreo.”

The fix is simple: clean your air fryer thoroughly and regularly, paying special attention to hard-to-reach areas where residue accumulates.

Read more: Your Air Fryer Might Be Working Against You—Here’s the Easy Fix