Cooking can affect the nutrients content of vegetable by simply the way of how it is being cooked. Vegetables are one of the highest food that would give us tons of supply of nutrients but when we add preservatives and such into it, then its nutrients would reduced. So rather than cooking vegetables into something like chips or etc., why not eat it fresh? Eating fresh vegetables without anything unnecessary added to it would be healthy for us. In my home, we just wash the veggies and even just boil it and then eat it raw. That way, our health is guaranteed.