leifw

Omega-3 fatty acids are generally recognized as healthy. Mercury is generally recognized as toxic. Seafood tends to contain both. Because I'm that kind of nerd, I figured out the optimal fish to eat to increase omega-3 intake while limiting mercury exposure. Here's a sorted list of the ratio of Omega-3 fatty acids to mercury in common seafood. A higher ratio is better.

	Mean Mercury (ppm)	Mean Omega-3 fatty acid (g)	Omega-3/Hg (g/ppm)
Salmon (fresh,frozen)	0.01	0.68	68
Herring	0.04	1.76	44
Flounder or sole	0.05	0.43	8.6
Pollock	0.06	0.43	7.166666667
Crabs	0.06	0.37	6.166666667
Canned tuna (light)	0.12	0.495	4.125
Catfish	0.05	0.175	3.5
Scallops	0.05	0.17	3.4
Halibut	0.26	0.7	2.692307692
Fresh or frozen tuna	0.38	0.76	2
Cod	0.11	0.185	1.681818182
Shark	0.99	0.9	0.909090909
Lobster	0.31	0.235	0.758064516
Swordfish	0.97	0.7	0.721649485
Mahi mahi	0.19	0.12	0.631578947
Tilefish	1.45	0.8	0.551724138
King mackerel	0.73	0.34	0.465753425
Red snapper	0.6	0.27	0.45
Grouper	0.55	0.21	0.381818182
Orange roughy	0.54	0.002	0.003703704

Data is from the American Heart Association.