Is it safer to cook eggs in cast iron or a nonstick pan?
Cast iron is the better everyday choice when it is well seasoned. Use care if you have been told to limit iron.
What's actually in it
Most nonstick pans use a PTFE coating. PTFE is the slick surface that helps eggs slide. Cast iron is different. It is iron with a thin layer of baked-on oil called seasoning.
For eggs, a well-seasoned cast iron pan is a good swap because there is no plastic coating to scrape. Heat matters, though. Use medium heat and a little butter or oil.
What the research says
A 2025 Journal of Hazardous Materials lab study found PTFE micro and nanoplastics entered intestinal cells and caused oxidative stress, mitochondrial damage, inflammation, and DNA damage.
A 2021 systematic review in Nepal Journal of Epidemiology found cooking in iron cookware can raise the iron content of food. That can help some people, but it is not right for everyone.
A 2025 International Journal of Environmental Health Research study found metal release from cookware changed with pH, and acidic or alkaline test liquids increased release from several materials, including cast iron.
For eggs, cast iron is a solid choice. Use a wood spatula to protect the seasoning. If your pan is rusty, shedding black flakes, or used for long tomato or vinegar-heavy cooking, clean and reseason it before making eggs.