Use a non stick frying pan for your cooking so that you do not have to add oil. The golden rule is to try and avoid as much oil as possible and a non stick pan is the perfect solution to this problem.
Boil your vegetables instead of cooking them, or even better, eat them fresh. However if you do not like eating your vegetables as it is, try steaming them without adding anything at all. This is probably the healthiest way to eat cabbages, cauliflowers and a host of other vegetables.