Risks Involved in Eating Fish, Shellfish and Other Seafood.
We hear a lot about the health benefits about eating fish. But there is a downside too
The risk of mercury contamination in fish has been known for a number of years. Fish and sea mammals are almost the only source for mercury poisoning in humans. Mercury poisoning affects the nervous system and is especially harmful to children. Mercury poisoning can interfere severely with the healthy development of the nervous systems of children.
What's so nasty about Mercury
The main reason for this is that mercury is a very powerful “neurotoxin” that can cause severe problems in the development of the brain, spinal cord, and nerves throughout the body. And that is harmful especially when the nervous system is “under development” as it is in children. But when you take the FDA recommendations you find further down in the article to mind there will be no problem.
Adults are less vulnarable
For adults things are less alarming. Really high Mercury levels can result symptoms like tremor, difficulty with concentration, and vision deficits, among others. But to get to this point you really have to eat a lot of fish. It’s a bit like discussing the possibility of getting drunk from apple juice you forgot to put in the fridge and drink a few hours later. There will be alcohol in the juice, but to get some effects you will have to drink a few gallons of it.
Seen in this light, the mercury in fish will not undo of the positive effects of Omega 3 fatty acids and actually set you on a course of heightened risk for coronary disease.
The Cumulative nature of Mercury Levels
Mercury contamination is cumulative. This means that, due to the greater consumption of mercury over a longer period, larger and more predatory fish contain higher levels of mercury in their bodies than smaller fish. Also, the level of mercury found in fish and seafood depends on their aquatic location and of course their place in the food chain.
According to the US Food and Drug Administration (FDA), the highest mercury levels found in consumable fish include those found in sharks, swordfish, tilefish and frozen tuna.
There has been additional analysis of canned tuna that reveals higher mercury content in canned white albacore tuna than in canned light tuna.
In the January 2004 issue of Science Magazine an alarm was raised over farm-raised salmon. Salmon is a fish that contains very high Omega 3 levels. The article expressed a concern over the level of cancer-causing pollutants found in farm-raised salmon. In wild salmon, those pollutant levels are significantly lower.
Still further investigation by the FDA revealed that there in no cause to stop eating fish because of this. The positive effects this meat has on us far outweighs the risks.
There are huge health benefits related to eating fish regularly. At this time, we have more data on the benefits as well as the risks of eating fish and seafood.
Scientists don’t know at what levels contaminants become dangerous to humans, but they do agree on the beneficial nature of the nutrients found in fish. The experts are certain about the fact that regularly eating fish is beneficial to your health.
Here are two FDA tables about safe fish as well as the more risky ones high up in the food chain.
FDA Top 10 Safe Fish and Shellfish
- Light Canned Tuna
- Flatfish (like flounder, plaice and sole)
FDA Risk Assessment for Pregnant Woman, Nursing Mothers and Children.
Do not eat:
- King Mackerel
Eat up to 6 ounces a week:
(1 average meal)
- Albacore White Tuna
- Locally caught fish from lakes and coastal waters
Eat up to 12 ounces a week
(2 average meals)
- Canned Light Tuna
When it comes to tuna, there are some important points. Try to get tuna from the Pacific Northwest. The mercury levels of tuna steak, sushi grade tuna and canned Albacore Tuna get higher as the fish get bigger, or if they live in more polluted water.
Tuna from the Northwest is usually caught in cleaner water and is fished on a smaller scale. The average size of the fish in some smaller canneries in the Northwest is around 15 – 20 pounds instead of the 40 – 50 pound average of the major canneries.
Most experts do agree that fish is healthy and that the risks are minimal when compared to the benefits. Take the advice of not eating very large fish high up in the food chain to heart.