As most of us know the fatty acids contained in fish are considered critical for a healthy body and mindm but if you've been eating fish either canned or fresh you might have more in common with this guy than you ever would've guessed. So, what exactly do you, the health conscious fish eater have with the first Qin Dynasty emperor? Simply put, mercury.
The early Qin Shi is thought to have died from mercury poisoning after consuming mercury laced tonics in his fruitless effort to become immortal. Unless you want to retry his fateful immortality experiments it is important that you make informed decisions on the amount and type of fish you consume.
Although there are very specific guidelines given by the FDA that track average mercury levels in commonly eaten fish that you should look at, a simple rule you can follow is to eat fish at the bottom of the food chain. Although the mechanism by which mercury accumulates in fish contains several variables such as location, diet and levels of fatty tissue, in general fish that eat other fish will contain higher levels of mercury than fish that don't.
Take for example the diet of swordfish versus sardines, the FDA cites the mercury concentration in swordfish at 0.976 parts per million compared to sardines at 0.016 parts per million. As you could guess the diet of a fish that has a sharp pike attached to is generally predatory with its staple diet including octopus and mackerel, compared to the sardines, who often have no teeth at all and instead filter feed plankton. The same comparison can be done with shark and anchovies, with similar results.
Besides diet, another important factor that contributes to mercury levels in fish is the average life cycle of the species. The longer a fish has lived the greater the chance for high levels of mercury accumulation.
This information is especially important for women who are either pregnant or could become pregnant in the future. Just as in fish, mercury levels in humans can take years to naturally dissipate once consumed, potentially causing harm to a fetus.
So next time you are looking for a fishy treat, remember two things, mercury won’t make you immortal and do your best to always eat fish with short life cycles at the bottom of the food chain.