Which cooking oil should I use?

and are there "bad" ones?

I don’t have an air fryer, but one of my qualms about them is that they use very little oil. I know what you may be thinking - but oils are “bad” anyways! Less oil and fat is better! But this thought hurts my dietitian heart, and that’s because some plant oils are wonderfully health-promoting and we should be including them in the diet regularly. As per…