Mercury- Neurotoxin from the fish
Mercury is an industrial toxin and the most neurotoxic substance known. Plankton will absorbe it from seawater and initiate bioaccumulation in the food chain.
Milos Pokimica
Written By: Milos Pokimica
Medically Reviewed by: Dr. Xiùying Wáng, M.D.
Updated June 9, 2023We are being taught to think of fish as a healthy form of meat or at least a form that is a healthier and better choice. The reason is that fish has all of the healthy omega-3 fatty acids that we need for our brains. We need to get omega-3 fatty acids from food to prevent age-related cognitive decline. There are no omega 3 inland animals if there are not deliberately fed with flaxseed like in the case with omega 3 eggs. Omega 3 eggs are like conventional eggs except that chicken feed is supplemented with an omega-3 source like flax seeds. Fish get them from algae that actually produce them and then when fish eat algae it will get passed around through the food chain. Also, fish tends to have fewer calories than other meat sources but that might not always be the case.
The problem is that there are more than just the omega-3 fats in fish that comes from seawater. Everything that is in the water no matter how minute the concentration the algae will filter out and concentrate tens and hundreds of times more. One thing that will be present in seawater that is not present in freshwater and that plankton will pick up, and also algae, and that will then bioaccumulate in the food chain is one of the most neurotoxic substances known to mankind. Mercury.
We are being taught to think of poisons in a dose-dependent manner because that is how modern medicine works. Something is poison, but it has a low concentration so it is ok. Some side effects and so on. “The dose makes the poison” (Latin: “sola dosis facit venenum”). It is an adage intended to indicate a fundamental principle of toxicology. It is credited to Paracelsus, the alchemist, and father of modern medicine. Now, this is correct for some chemicals but not for all of them. Some toxins do damage, and I will argue most of them do damage in any exposure. This means that if we ingest even one molecule of a substance, it would cause damage. That damage would not be enough to kill us, but the damage will happen.
An excellent example of this is mercury. It is so toxic for our brain that it kills brain cells upon contact. Neurologic damage is most severe in utero. Mercury upon contact with neurons causes neuronal atrophy. When it enters the brain no matter what concentration, even one atom of it, it will do severe damage. If exposure is significant, it will cause severe neuronal atrophy with no chance of recovery. Long-term studies have demonstrated that even minuscule prenatal exposure at very low concentrations can cause a detectable loss in the areas of memory, language, and motor function. Children are so sensitive to it, so if affected, they may have hearing loss, visual loss, seizure disorders, developmental delay, and long-term stigmata including motor impairment. For a pregnant woman, it is forbidden to eat tuna in any amount. Also, your brain and body can be exposed to toxic mercury through a number of other ways as well, from getting a flu shot to having a dental filling. To be reasonable here, one can of tuna has more mercury in it than 100 vaccines. Studies have found that people with amalgam dental fillings can have mercury vapor concentrations ten times higher than those in people without them.
Fish consumption provides nutrients but also provides methyl-mercury. All marine fish, not just tuna, contain methylmercury (MeHg), some more and some less. Because the toxic effect of mercury is most destructive during brain development, prenatal exposure is of the most significant concern. Mercury is a cardiac toxin as well, not just the brain one. I will give an example here to put things into perspective.
In this study (Oken et al., 2008) they analyzed connections of children’s susceptibility to mercury both from pregnancy exposure from mother and from fish consumption. Thimerosal from vaccines was looked into as well as dental amalgam impacts on child neurodevelopment. Vaccines in the past used something called thimerosal, which is a preservative containing mercury. To put this into perspective.
Eating a single serving of tuna had the same mercury level as 100 (one hundred) thimerosal vaccines.
The summary of the study was:
“Exposure to mercury may harm child development. Interventions intended to reduce exposure to low levels of mercury in early life must, however, be carefully evaluated in consideration of the potential attendant harm from resultant behavior changes, such as reduced docosahexaenoic acid exposure from lower seafood intake, reduced uptake of childhood vaccinations, and suboptimal dental care.”
Thimerosal has been taken out from most of the vaccines young children get in 2001, with the exception of the flu vaccine, which still contains small amounts. However, how about something one hundred times worse. One single serving of canned tuna. How many servings have we eaten in our lifetime? How about all the other fish? It is not just tuna, all fish has mercury some more some less and it is not just mercury. I use mercury here only as an example. There is a whole list of other heavy metals like mercury that will remain in our ocean for eternity and will never biodegrade because they are elemental particles. Also, there are a thousand other non-organic resistant pollutants that also didn’t degrade and bioaccumulate and microplastic, and the list goes on. The reason this toxin is highly concentrated and highly toxic in such levels in tuna is that tuna is a predatory fish at the top of the food chain. On the bottom of a food chain are plankton and algae that filter the seawater and then the concentration will get ten to a hundred times that in the water but that will still be low. Then these substances start to accumulate as we move up the food chain. As the bigger fish eat the smaller fish it eats all of its toxins as well. When we arrive at the top of the food chain the situation is as it is. The only solution is to go low on the food chain.
Do not eat meat from the oceans, and especially do not eat predatory fish like tuna. Even molecularly distilled DHA supplements are proven to be polluted with heavy metals and toxins. Even krill oil people have begun to substitute instead of fish oil to avoid pollution was proven to be polluted. Krill has a very short life and krill oil was still highly polluted. If you want omega 3’s then just eat flax. Flax has lignans that have a wide range of health benefits including breast cancer prevention and minerals and fiber and is one of the healthiest food items you can get. If you want a supplement as a vegan you can still get algae-based DHA oil. Never and I will repeat this never eat anything from the sea even if you are pregnant or if you are a child if it is from the oceanic animal kingdom ever period, vegan or not. If you eat tuna and expecting a baby you just lowered your baby’s IQ by a measurable amount or worse.

There was a big public concern and mistrust in vaccines and the possibility of links with autism and other diseases. However, there was no public outcry about fish consumption. Fish toxicity is the number one source of mercury in the world. Mercury in fish is so concentrated that by all accounts some of the fish species should be forbidden by law to be used as human food. One single serving is worse than all of the vaccines your child will receive in your life if we look at mercury levels only that is.
What about cadmium?
What about PCBs, PBDEs, dioxins, and chlorinated pesticides?
Because mercury is a neurotoxin, it was thought it was the underlying cause of the connection between autism and vaccination. Today more children get autism even without mercury in vaccines and the estimate is that this number will grow. This is a big subject to analyze, and I will say that most vaccines can be dangerous just by themselves and can cause harm but they do save a lot of lives and in the end, it remains the question of trust in the companies that supply those vaccines.
References:
- Oken, E., & Bellinger, D. C. (2008). Fish consumption, methylmercury and child neurodevelopment. Current opinion in pediatrics, 20(2), 178–183. https://doi.org/10.1097/MOP.0b013e3282f5614c
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Milos Pokimica is a doctor of natural medicine, clinical nutritionist, medical health and nutrition writer, and nutritional science advisor. Author of the book series Go Vegan? Review of Science, he also operates the natural health website GoVeganWay.com
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Milos Pokimica is a health and nutrition writer and nutritional science advisor. Author of the book series Go Vegan? Review of Science, he also operates the natural health website GoVeganWay.com
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