What should I do if I am worried about mercury?
In the chart with the story at left, stick with the species that have the highest numbers on the left side. You can eat a lot of salmon without worrying, but not much orange roughy.
What if I want to load up on the omega-3 fatty acids that benefit fetal development and cardiovascular health?
Look for species that have the largest numbers on the right. Again, salmon is a great choice.
Why not eat salmon every day?
Government experts stress the importance of eating a variety of seafood. You will get different nutrients, such as selenium, which is important to brain function. Variety also lowers the risk of contaminants that might be present within certain species. Imported shrimp and catfish, for example, have occasionally contained carcinogens and antibiotics. Some farm-raised salmon may contain PCBs and dioxins, though that has fallen off since industry controls went into place.
Why not get omega-3s from nuts?
The two types of omega-3's that seem to be most beneficial occur mainly in seafood. In some circumstances, the body can produce the same omega-3s from nuts and vegetables.
What about fish oil and other supplements?
Fish oil, enriched eggs and other supplements that contain DHA and EPA fatty acids may deliver omega-3 benefits similar to seafood. Excessive use in diabetics may reduce sugar control. Some obstetricians recommend supplements as an acceptable omega-3 tradeoff for pregnant women.
How long will mercury stay in my body?
Half of the mercury now in your body should be gone in 60 to 90 days if you don't take in any more. It should all be gone in 10 months. The more you sweat, the faster it goes.
Stephen Nohlgren and Stephanie Garry, Times staff writers