Oils oxidize when they come into contact with the air (become rancid). Since almost all oil is continually exposed to some air from the time it is produced, the process of oxidation has begun in even the freshest oil. These oxidized oils cause inflammation and cell damage.
Although they’re usually refined, even unrefined and cold-pressed versions of these oils pose the same health risks, because the oils are naturally rich in polyunsaturated fats (PUFAs). The molecular structure of PUFAs makes them very unstable in the human body, where they generate a tremendous amount of free radicals—chaotic reactions that damage cells.
Free radicals are a normal byproduct of metabolism that our bodies are equipped to handle, but only up to a point. Seed oils produce an onslaught that far exceeds our innate capacity. Free radicals are bad for us in the same way that radiation is bad for us.When you eat a lot of PUFA-rich seed oils it’s like you have dirty bombs inside your cells