Packed with protein, omega-3 fatty acids, vitamins, and minerals, fish is an excellent source of nutrients for our body.
Unfortunately, mercury pollution within the environment has made its way from land to sea, contaminating nearly all of today's sea life.
Most of the mercury pollution in the US is a result of coal-burning power plants. Coal is naturally contaminated with mercury. When burned, it releases the mercury into the air. Environmental factors, such as rain and snow, then cause atmospheric mercury deposits to settle onto our land or even directly into our oceans. Inland pollution is also a great threat to marine life, as it is often carried out into the ocean by means of runoff from streams and rivers.
According to the Natural Resources Defense Council (NRDC), across the US, mercury pollution has contaminated 18 million acres of lakes, estuaries, and wetlands (43% of the total) and 1.4 million river miles!
While bottom dwelling fish initially ingest the mercury, the toxic element then works its way up the food chain when larger fish feed on the smaller. This is able to happen because mercury is bioaccumulative. In other words, it is stored in the fatty tissue of an organism and builds up gradually. An organism's body can release toxins on its own at a certain rate. However, if the consumption of a particular toxin is greater than the rate in which the body can flush it out, it will continue to build up. Even if a particular fish never actually eats the mercury deposits from the seafloor, they are eating the bodies of other fish that have already been poisoned, thus contaminating their own body. The same goes for humans consuming fish.
When humans consume an excess of mercury, it acts as a neurotoxin, meaning it interferes with the brain and nervous system. While everyone should be careful to not over consume food products with mercury, it is especially important for pregnant women, nursing mothers, and young children to keep their intake to a bare minimum. Brain development is taking place at a rapid rate in babies and children, which means nutrients are quickly and constantly being absorbed. Too much mercury can result in delayed development. Learning disabilities as well as delayed walking and talking are possible side effects. While an average adult should be fine eating 3-5 servings of low mercury fish per week, pregnant women and young children should have no more than 2.
Eliminating seafood entirely from your diet isn't necessary; it's just about moderation. Chemicals and toxins are present in many of the foods we consume nowadays. So, it's all about making smart choices to keep our bodies as toxin-free as possible, while still being able to enjoy all the wonderful benefits from nutrient-dense foods.
Below are a few helpful lists of the best, second best, and worse choices when it comes to selecting seafood. For a full and more extensive chart of fish and their mercury content, check out this awesome guide featured on the NRDC's website!
Top 10 Best Choices:
1. Salmon (canned and fresh)
4. Trout (fresh water)
5 Second-Best Choices (no more than 6 per month):
1. Halibut (Atlantic and Pacific)
3. Mahi Mahi
4. Tuna- canned, chunk light*
(Canned tuna is the most commonly consumed fish in the U.S. An average adult should be fine consuming up to 2 cans of chunk light canned tuna per week. However, canned albacore tuna has a much higher mercury content. Adults should limit their intake of albacore to no more than 3 cans per month.)
5. Bass (striped and black)
Top 5 Worst Choices:
3. Tuna- Big eye and Ahi
5. Mackerel (King)