Eating fish is good for the brain

There are two friends talking to each other in the bar.

A, “Do you know that eating fish contains a lot of Omega-3 acids. It is good for the brain and can increase intelligence.”

B, “Really! I need to eat more fish from now on.”

A, “Actually, there is no need for you.”

A, “Really. You think I am really very smart?”

B, “No. I mean for your intelligence, you will need to eat a whale.”