Does anyone know if the tuna served at subway has a good source of omega-3?

I usually like to buy this sub from subway, but I really don't feel any benefits I read about when it comes to tuna's omega-3 co-relation. There's tons of research supporting the health benefits of omega-3 on the brain. What should I supplement my diet with in order to gain the most of the benefits that omega-3 or any "brain food" has to offer?|||I would say the tuna has a good source of omega-3,at the end of the day its fish.i have started taking omega-3 supplements (capsules) i dont feel any different though and i have been taking them for a month.Pilchards is also a good source apparently.