A number of lawsuits have been filed in the USA alleging that fish oil products do not contain fish oil, JD Supra reported on 9 June.

Filed in California federal courts, the lawsuits targeted well-known dietary supplement products, such as Dr Tobias Omega 3 Fish Triple Strength (by Mimi’s Rock) and GNC-brand Triple Strength Fish Oil (by International Vitamin and Nutra Manufacturing), according to the report.

The allegations focused on the process used to create fish oil supplements—transesterification, JD Supra wrote.

Transesterification is a chemical process used to obtain fatty acid ethyl esters from fish oil achieved by introducing an alcohol catalyst to the fatty triglycerides.

The lawsuits claimed that the transesterification process intrinsically left the finished supplement products without any of the omega-3 fatty acids DHA or EPA, the report said.

The plaintiffs also alleged that the resulting omega-3 molecules in the finished post-transesterification product were different to the omega-3 molecules naturally found in fish oil, JD Supra wrote.

As a result, the lawsuits claimed that “once trans-esterified, fish oil is irrevocably transformed, such that it is no longer fish oil and therefore cannot be so named or labelled.” For this reason, the plaintiffs claimed that these products misled the public with false and deceptive labelling that was in violation of federal and state laws.

The lawsuits were still in their early stages, according to JD Supra, but the potential impact was substantial with fish oil supplements representing a large consumer market.