Sustainably caught fish is one of the greatest sources of omega 3's and protein out there. Omega 3's are known to play very important roles in brain health, heart health and bone health.
When buying fish, look for the Marine Stewardship Council (MSC) certification to assure you're buying delicious guilt-free fish. I'd also suggest watching Chef Dan Barbers TED talk - How I fell in love with a fish - you'll love it.
Here's a Salmon recipe for your delight: