French fries! Heavens, between the carbs and the grease they'll kill you! Pass the fish and those good ol' omega-3s.
Not so fast. I haven't heard much about it lately, but back in the late 60's/early 70's we heard incessantly about mercury pollution in our fish. Whether related or not, a trip down Lake Shore Drive in Chicago might well suggest that something was wrong - dead fish were always washing up on the beaches by the millions. Yecch.
It so happens that the mercury is still out there in high enough concentrations to get you under the right circumstances. People porking out on certain fish, usually in the name of health, are coming down with symptoms of mercury poisoning, and there are govt advisories on consumption of certain types of fish.
Here Glenn Reynolds notes Ukrainian candidate Yushchenko's dioxin poisoning and links to this, which suggests that use of "fake fat" (olestra), can help him clean the dioxins from his body and thus recover. Incidentally, the same thing might work for other bugbears such as DDT and PCBs.
Biochemical processes are very complicated, but in essence the above works because the substances are fat-soluble. They accumulate in your fat, and in turn they can be absorbed in other fats like olestra. Olestra does not remain in the body, any fat-soluble substances like the above it absorbs in its passage will leave the body with it.
And it so happens that the form of mercury that you get from the fish is fat-soluble. So maybe olestra could help clean out excess mercury too.
Now if only it made good french fries...