So, we’ve established that the good fats are - monounsaturated and polyunsaturated fats, which can be Omega 3 & 6.
But what’s the healthiest fat to cook with? Interestingly, fatty acids can start to break down when they’re heated and reach their ‘smoke point.’ The higher the smoke point, the greater the stability of the fat.23
Refined oils, e.g. any plant oil that isn’t described as ‘virgin’ or ‘extra virgin’ are the healthiest option, as they tend to be more stable at high temperatures. Meanwhile, oils with more monounsaturated fats, such as rapeseed and olive, are less susceptible to heat. Rapeseed oil and inexpensive olive oil are therefore the best choices for cooking.
Summary
Refined oils are the healthiest fats to cook with because they don’t tend to break down when they’re heated and reach their ‘smoke point.’ Rapeseed oil and olive oil (not the virgin or extra virgin variety) are the healthiest fats when it comes to cooking with fats.