The FDA is getting ready to change it's recommendations that women and children limit the amount of mecury laced seafood they eat. Personally, I'd like to avoid bio-accumlitive neurotoxins in my diet, especially until we have our children. But maybe that is just me!
They say that the benifits Omega-3s and Selenium (among other trace minerals) found in fish may outweigh the damage from the mecury. But given that the levels being found in people are higher then once thought I think I will pass. There are other ways to get these nutrients!
One 3-1/2 ounce serving of tuna has almost 100% of the daily recommended selenium level at 63 micro grams. But just one ounce of Brizal nuts blow them away with over 700% of the daily remmendation!
For all trace minerals you are liable to found more in foods grown on farms that have not been in industrial agriculture for decades, like those grown by farmers you are likely to meet at your farmer's market!
And while you are there pick up some grass fed beef! While it is true that wild caught fish have Omega 3 levels that blow grass fed beef out of the water, most people eat mainly farmed fish! Micheal Pollan points out in Ominovore's Dialmma that it is not so much what you eat but what you ate - ate... If your salmon is feasting on corn you might as well be eating Chicken...
And while you are at it eat some flax seed every day!