According to the report – only available to ConsumerLab.com members – tests of fish, krill and algal oil supplements revealed quality problems with 7 out of 24 products. Three products contained less of the omega-3 fatty acids EPA and/or DHA than claimed, and spoilage was detected in one of these products as well as in two others, including a children's supplement. One supplement released its ingredients too early, while another for pets exceeded the contamination limit for PCBs.
"Supplements providing EPA and/or DHA are a great alternative to fish as a source of beneficial omega-3 fatty acids, as they typically have far fewer contaminants, cost less, and are more convenient to obtain," said Dr. Tod Cooperman, ConsumerLab.com's president, in a statement. "But products vary in quality, strength, odor reduction, and price, so you need to choose carefully."
ConsumerLab.com also reported the following findings:
- Labels on some products included terms such as "pharmaceutical grade" and "tested in FDA approved laboratories," which are meaningless, as there is no basis for either claim.
- A krill oil supplement that failed for both spoilage and low omega-3 levels claimed to be quality assured under GMPs (good manufacturing practices). Another "krill oil" supplement contained more fish oil than krill oil.
- Most products met ConsumerLab.com's strict contamination limit for dioxin-like PCBs of 3 picograms per gram (3 parts per trillion). However, one product, a pet supplement, slightly exceeded this limit with 3.14 picograms per gram. However, this exposure is still very small compared to that from fish meat -- a small serving (3 ounces) of fatty fish such as salmon may easily provide 170 picograms of dl-PCBs as well as a significant amount of mercury. Trace amounts of dl-PCBs were found in all supplements, despite claims from some of being free of contaminants. There was no detectable mercury in any of the supplements.
- The cost to obtain 100 mg of EPA and/or DHA from fish oil ranged from about 1 cent to 15 cents among fish oil supplements, and was about 30 cents from krill or algae oils. A fairly standard daily dose of 500 mg of EPA and DHA from a quality-approved product could be obtained for as little as 6 cents. Higher prices were not associated with higher quality.
- Concentrations of EPA and DHA ranged from less than 20% to more than 80% of the marine oil content listed on front labels -- which is why consumers should specifically look for the amounts of EPA and DHA that typically appear on side labels.
A recent survey by ConsumerLab.com showed that fish oil had become the most commonly used supplement among people who regularly use supplements (74% of respondents) -- exceeding, for the first time, the use of multivitamins. U.S. sales of fish oil supplements in 2009 were $976 million, up 20% from the prior year, according to Nutrition Business Journal.
Some in the supplement industry have suggested ConsumerLab is biased because, in addition to conducting independent testing for its reviews, it also tests for companies who pay to have their products certified. Yet the results of this report, and especially its cautions, should give all health-conscious consumers pause.