If you’ve been taking a fish oil supplement for ages and no other oils, then you’re only addressing a very small part of the requirement that your body (and brain) has for the right fats and oils. The body has such a great requirement for these essential oils that we need to take them as a foundation to our fat and oil needs. Then, if you choose to take a fish oil supplement on top of this foundation, you can meet all your oil needs. However, please remember that fish oil also undergoes processing damage, so you may wish to look at an alternative to fish oil. However, the foundation oils have to be the basis of your oil supplementation.