FW20017: Food Safety During Pregnancy
Most foods and drinks are safe to consume during pregnancy. But there are some products pregnant women should be careful with or avoid. Public Health and Food Safety authorities in most OECD countries provide risk communication material related to food safety during pregnancy. Such a resource is available on the New Zealand Food Safety (NZFS) website.
However, this advice was published in 2007 and was based on information available then. Since that time a range of new foods has been introduced and become popular in the diet of New Zealanders, while there is improved understanding over which foods might be a risk.
NZFS wants to ensure the food safety advice for pregnancy remains current with the latest science and dietary practices for New Zealand.It is important that food safety advice for pregnant women captures all of the foods that could be a risk, however it needs to balance this with ensuring pregnant women can maintain a varied diet and have access to the widest source of nutrition without being overly restrictive.
To achieve this a research project was commissioned to the Institute of Environmental Science and Research Limited (ESR) to provide a scientifically robust background for updating food safety advice for pregnant women. Food safety considerations are focused on Listeria monocytogenes, Toxoplasma gondii, mercury and caffeine, as these four hazards have known specific impacts on the foetus.
Other microbiological and chemical hazards were not targeted as the risks are not pregnancy specific and food safety advice for the general public is also applicable for pregnant women. This report is restricted to food safety issues and does not cover advice on healthy nutrition during pregnancy.Maternal exposure to the microbiological hazards Listeria monocytogenes and Toxoplasma gondii is strongly linked to adverse effects on the foetus. For two other microbiological hazards, Salmonella spp. and Campylobacter spp., associated with adverse outcomes specific to the pregnancy period, the supporting epidemiological evidence is weaker.
The report has examined up-to-date information on these two other hazards and provided safety advice where relevant.The research examined data on complex changes in the maternal immune system that include both down regulation and up regulation of aspects of the immune system. Evidently pregnant women may be more susceptible to some infections than non-pregnant women, but no more susceptible to most types of infections. However, the complications of common infections in pregnant women can be more severe.
The main outcome of the research is an evaluation of evidence for food safety advice during pregnancy. The report included an evaluation of all food groups listed in the current New Zealand Food Safety’s guide to food safety in pregnancy. Consideration was also given to a small number of foods that were not previously evaluated in relation to pregnancy. Additional advice was proposed for these foods. NZFS agrees with the suggestion that advice should
New Zealand Food Safety Food Safety During Pregnancy be included in the guide for sprouts, recommending that these foods are not eaten unless cooked; for dried herbs recommending thorough cooking and a recommendation to not drink unpasteurised fruit juice and cider (non-alcoholic). The report confirmed that in most cases, New Zealand Food Safety’s advice on foods to eat or not eat during pregnancy are consistent with the available scientific evidence.
In a small number of instances, suggestions were made to better align the advice with the current available evidence. NZFS agrees with these suggestions and intends to expand the advice accordingly. Based on the evidence provided NZFS agrees that the current advice related to low acid soft pasteurised cheeses (e.g. Brie, Camembert, blue, ricotta, mozzarella, feta) should be strengthened to recommend that pregnant women do not eat these cheeses unless cooked.The report supports NZFS’s intention to make its advice on a range of commercial pasteurised dairy products with relatively short shelf-life less restrictive. Currently the advice is to dispose products like pasteurised milk or yoghurt after two days of opening.
The reviewed scientific evidence identified that, if that the products are refrigerated in original packaging and care is taken not to contaminate lids when using, it is safe to follow manufacturer’s advice on the package. Suggested modifications will allow pregnant women better planning of their daily diets and will also reduce unnecessary food wastage.
The report has suggested the current advice related to soft serve ice cream be reconsidered. However, NZFS’s opinion is that, given the likelihood of Listeria sloughing into the product through its processing, current advice to avoid this product during pregnancy is adequate. For some foods the scientific evidence is not currently strong enough to support specific food safety advice on these foods, although the available evidence suggests they may represent potentially emerging risk foods for pregnant women. A brief summary of such foods is provided at the end of the report. NZFS will follow up on any new scientific research related to these products.