Fish Oil Supplements: Buyer Beware of Dangerous Brands



fish oil contamination

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Earlier this year, the New York Attorney General charged Target, GNC, Walmart and Walgreens with removing certain supplements from the shelves.

Specifically, these stores were given cease and desist letters to stop selling ginko biloba, St. John’s Wort, ginseng, garlic, echinacea and saw palmetto.

Why?  Because quality testing demonstrated that these supplements either did not contain the labeled ingredient or contained ingredients not listed on the bottle.

GNC’s corporate response?  They stated that they stand by the quality of their products.  Huh?  I’ve got a feeling that they’ve lost some corporate integrity over this entire episode by showing how disconnected they are from what was happening.

While this action by the New York Attorney General was related to a short list of supplements, it is likely that this quality control issue cuts across many other supplements that you can buy at non-physician outlets.  This problem is probably greater at retail outlets that do not focus on supplements, although the inclusion of GNC into the cease and desist order certainly questions GNC’s overall quality control process.

Each supplement has its concerns.  When it comes to fish oil supplements, the contamination with polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) is of concern.  The higher quality supplement companies will go through expensive and time consuming molecular distillation procedures to make sure that their fish oil supplements will be free from these contaminants.

But really—if these higher quality supplements cost more (sometimes twice as much), is it really a big deal if there’s a few extra “treats” in the fish oils?

That very question is addressed in this particular study.  In this rat study, researchers looked at the effect of contamination of fish oils with PCBs and OCs on cholesterol levels, inflammation (as measured by hsCRP) and oxidative stress.  The rats where given either “clean” fish oil, contaminated fish oil or corn oil (as a control).  Here’s what they found:

  • After 9 short weeks, there was an accumulation of PCBs and OCs in the fat tissue of the group given the contaminated fish oils.
  • On the plus side, as expected, both fish oil groups had higher HDL cholesterol with lower triglycerides, LDL cholesterol and C-reactive protein.
  • Unfortunately, in the contaminated fish oil group there were higher levels of damage to cholesterol (as measured by lipid peroxidation).
  • The contaminated fish oil group also had less antioxidant capacity.

So, while the contaminated fish oils were doing their expected job of helping lower cardiovascular disease risk factors, in the background problems were brewing.  This damage to fats (lipid peroxidation) and loss of antioxidant reserves is not a good thing and can actually do far more damage to your body in the long run.

As a physician who sells physician-level supplements in my office, this article may seem a little self-serving, but this study should certainly give you some food for thought when it comes to buying your fish oil supplements with a focus on cost rather than quality.  Always make sure that you are buying supplements that have the quality control aspects either on the bottle or readily available on the manufacturer’s website.

If your health really does matter, it pays to make sure you get good quality for your money and not just finding the cheapest fish oil you can find.  Just in case you don’t have access to a physician who sells higher quality fish oil supplements, Nordic Naturals is a brand that can be found at many health food stores or online at Amazon.

James Bogash

For more than a decade, Dr. Bogash has stayed current with the medical literature as it relates to physiology, disease prevention and disease management. He uses his knowledge to educate patients, the community and cyberspace on the best way to avoid and / or manage chronic diseases using lifestyle and targeted supplementation.







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