Both olive oil and rape seed oil contain the omega 3, 6 and 9 fatty acids known to reduce cholestral, help maintain a healthy heart, healthy brain and joint mobility. Rape seed oil has a much higher flash point (point at which oil burns/breaks down), which means it is better to use when frying, roasting etc than olive oil if you want to maintain its healthy properties. Unless you are using olive oil for it’s flavour then it is better to use rapeseed oil (in my opinion). From a food mile point of you this is also better, as great rape seed oils are produced in Oxfordshire and many other counties in the UK.