I used to take fish oil and flax oil, until I read that the fish oil already contains EPA and DHA-the essential oils that provide so many health benefits. Both oils are rich in omega-3's, but omega-3's must be converted to EPA or DHA by your body to become really benefitial. Since the fish oil already has EPA and DHA in it, I focus more on fish oil. Flax oil has a great overall spectrum of fat, though. It's hard to beat flax if you're on a super low fat diet-you definately need some flax every day. Fish oil is like a daily multi-vitamin, take some daily no matter what. I go kind of heavy with 6-12 g per day.