The Ministry for Primary Industries (MPI) and the Ministry of Health are confident a recent study provides no evidence of a food safety risk associated with fish oil supplements currently on the New Zealand market.
Jenny Reid, MPI Manager Food Science and Risk Assessment says the recently published Liggins Institute study that gave highly oxidised fish oil supplements to pregnant rats does not identify a risk to pregnant women.
"The fish oil that was given to the pregnant rats in the Liggins Institute’s study was artificially oxidised to an extremely high level, far higher than that found in fish oil supplements currently on the market. It is extremely unlikely that oxidisation of any product on the New Zealand market containing unsaturated fats would reach these levels," says Ms Reid.
In April 2015 MPI commissioned a review of the published data on the toxicity of oxidised fish oils. The review did not identify any concern.
The quantity given to the pregnant rats was greater than the recommended dose and therefore more than a human could, or should, consume within a day.
"The study does not identify whether oxidation of fish oil is a health risk in human pregnancy," says Ms Reid.
The Ministry of Health Acting Director of Public Health, Dr Stewart Jessamine, says its advice to pregnant women is, and always has been, to eat a healthy, well-balanced diet and where practical to get your essential nutrients from foods, not supplements.
"There is nothing in the study to suggest there is a risk to pregnant women. Consumers may choose to take dietary supplements, but the best source of omega 3 is from fresh fish. If people do not like fish then I encourage them to talk to a registered dietitian regarding other sources of omega 3," says Dr Jessamine.
Note: Any food with unsaturated fats in it will oxidise in air. For example butter will go rancid over time if exposed to air. Fish oils contain unsaturated fatty acids, but are marketed in capsules that limit their exposure to air. It is extremely unlikely the level of oxidisation would trigger a food safety risk. As always, consumers should follow the manufacturer’s instructions for storage and consumption.