Fish Oil Supplements Safer Than Fish
Friday, July 21, 2006
For optimal health of the whole body, including the eyes, the consumption of two or more servings of fish high in Omega-3 fatty acids per week is advocated by the American Heart Association, the American Medical Association, the FDA and the most recent edition of the peer-reviewed journal, Ophthalmology.
- PCBs: Colorless
and odorless chemicals widely used in electrical equipment such as
transformers before 1977. 1.2 billion pounds of PCBs in the
ended up in rivers and oceans and were concentrated in long-lived large bottom fish like halibut and sword fish, however lower concentrations have been found in all ocean fish, including tuna. US
- OCs: These are from the pesticides sprayed on crops and forests until around 1980. They were deposited in sediment, rivers and the seas and are still taken up by small fish and organisms today due to their resistance to degradation.
Humans have on average, 1.4 parts per billion of PBCs in their serum. Levels are higher in fatty tissue and breast milk. PCBs and OCs are stable and nonflammable as industrial agents with extremely long half-lives. OC pesticides concentrate 1,000-fold in fish and marine mammals. DDT and its metabolites have been detected in 94% of fish sampled.
PCB and OC Concerns:
- Neurotoxicity including tremors, seizures, headaches, vomiting, and dizziness. Chronic exposure can lead to reproductive, neurologic, hepatic, and carcinogenic effects. Lower IQ has been associated with in utero exposure to high levels of PCBs and OCs.
Organic mercury compounds like methylmercury can enter the body readily through lungs, skin and stomach. The main human exposure to mercury is through ingestion of fish that contain methylmercury.
- Both fresh
water fish and ocean fish contain high levels of mercury, PCBs, and OC pesticides. These levels increase with age and size of fish, therefore consumption of small fish is advised.
- Farm-raised salmon have significantly higher levels of PCBs, fat, and cholesterol than wild salmon and can lead to higher PCB intake than the allowable level.
- Unfortunately, mercury is found in equal concentrations in farm and wild fish.
Mercury is a potent neurotoxin, meaning it damages the nervous system. The "mad-hatters" of the 19th century suffered from mercury poisoning which caused severe personality changes, nervousness, trembling, and dementia. The hatters were exposed to mercury in the felting process, where mercury was rubbed onto cloth to preserve it.
Efficacy of omega-3 fatty acids in preventing age-related macular degeneration: a systematic review. Hodge WG, Schacter HM, et al. Ophthalmology, 2006 Ki;'113(7);1165-72 [ abstract]
Measurement of Mercury Levels in Concentrated Over-the-Counter Fish Oil Preparations: Is Fish Oil Healthier Than Fish? Foran S, Floor J, Lewandrowski K. Archives of Pathology and Laboratory Medicine; Vol. 127, (12):1603-05. [ abstract]
Potential role of dietary n-3 fatty acids in the prevention of dementia and macular degeneration. Johnson EJ, Schaefer EJ, Am J Clin Nutr. 2006 Jun;83(6 Suppl):14945-85 [ abstract]
Overview of the clinical toxicity of mercury. Magos L, Clarkson TW. Ann Clin Biochem 2006 Jul; (43) 257-68 [ abstract]