Eat Seafood At Least Twice A Week, Says Nutrition Expert

MEDIA RELEASE: 7 August 2008

EAT fish or other seafood at least twice a week for optimum health -- that’s the straightforward advice of nutrition expert Dr Shawn Somerset.

Dr Somerset, Senior Lecturer in Human Nutrition at Griffith University, has been studying the role of seafood in meeting the latest guidelines on healthy eating from the Australian Government’s National Health & Medical Research Council (NHMRC).

He said today that a switch to eating more seafood was a practical, cost-effective way of significantly improving the health of the average Australian.

“The health benefits of seafood are well established and internationally-recognised, particularly in relation to heart health,” Dr Somerset said. “A switch to seafood and away from other less nutritionally valuable foods could significantly extend lifespan and quality of life for many Australians.”

Dr Somerset recommended eating a variety of fish and other seafood at least twice a week, and, ideally, four times a week or more.

He also recommended portions of 200 to 250 grams rather than the standard portion of 150 grams.

“Eating fish or other seafood twice a week should be the minimum consumption level simply to avoid deficiencies in essential nutrients such as Omega-3 fat and iodine,” Dr Somerset said.

“However, to achieve optimum nutrition, I would recommend at least four meals per week of 200 to 250-gram portions of fish or other seafood. This is achievable, considering there are 21 meal opportunities every week.

“Potentially, this would make an enormous improvement to the health of the Australian community, given that surveys indicate that presently only 25% of Australians eat seafood an average of even once a week.”

Dr Somerset said seafood could make a very significant contribution to achieving the NHMRC recommendations for healthy eating.

“Seafood is a high-quality protein source and relatively low in fat. Its protein comes at the cost of fewer calories than most other meats, and so is beneficial in weight-reduction diets in particular, something very relevant now that obesity levels are causing such concern to health authorities in Australia.

“Also, seafood is a prime source of essential nutrients, particularly Omega-3 oils, iodine and selenium, and is also rich in zinc, calcium and Vitamin B12.

“Research suggests that many Australians, particularly children, are deficient in iodine, and, in the case of zinc, the NHMRC itself has described it as ‘borderline for adequacy in the community’. Seafood is an excellent source for both: all seafood in the case of iodine and Oysters in particular for zinc.”

Dr Somerset said that, in 2006, the NHMRC introduced new Nutrient Reference Values (NRVs), a set of recommendations for population intakes of nutrients based on the best scientific information available.

“These were an extension of the 1991 Recommended Dietary Intakes but involved key changes. These changes included addition of an expanded set of nutrient intake reference categories and an increase in the range of nutrients for which reference values were provided.

“For the first time, the NHMRC has formally recommended specific intakes of the essential Omega-3 fatty acids (oils), which make up the largest component in fish oil. The levels required to avoid deficiencies in Omega-3s can be achieved by eating two or three meals of 200 to 250 grams each of most types of seafood each week.

“This will also supply much of the average weekly requirements for other nutrients, such as selenium, iodine, zinc, copper and Vitamin B12.”

However, Dr Somerset said eating seafood more frequently would confer further benefits.

“The NHMRC went further than simply recommending the minimum average daily amounts of nutrients like Omega-3 fatty acids by also making recommendations on nutrient intakes to reduce chronic disease risk.

“Here, the NHMRC’s typical recommendation was to replace what it called ‘nutrient-poor, energy-dense foods and drinks’ -- in other words, foods low in nutrients but high in calories -- with vegetables, fruit, wholegrain cereals and lean protein like seafood.

“To optimise the disease-fighting benefits of Omega-3 oils, the NHMRC recommended average daily intakes of 610mg for men and 430mg for women, which are three to four times the minimum daily intakes recommended.

“That may seem like a lot to Australians at present but it is only half the average Omega-3 intake of the Japanese, and their high seafood consumption and consequent Omega-3 levels is attributed as the major reason for their comparatively low levels of heart problems.

“Here, it means eating varieties of fish with higher-than-average oil content -- fish like Swordfish, the Mackerels, Australian Sardines, Australian Herrings, Mullet, Tailor and Atlantic salmon -- and probably eating seafood four times or more a week. It can be included for lunch, even breakfast, as well as making up the centerpiece of evening meals.

“Consumers may find it helpful to talk to a specialist seafood retailer and to consult the publication Seafood the Good Food, published by CSIRO, which lists the oil content of seafood varieties sold in Australia.

“One simple thing to do, and this deserves to be emphasised, is to eat a wide variety of seafood and to eat it often.”

Dr Somerset has been studying how Australian fish and other seafood fit into the context of the new NRVs.

Specifically, he has prepared calculations for a range of popular fish and other seafood that estimate the amounts of each required to meet the nutrient reference values (NRVs) for a range of nutrients.

It is intended as a guide upon which evidence-based communication about the health benefits of fish and other seafood can be derived. It is not intended to be a promotional vehicle in itself.

“This analysis confirms that the NRVs for long-chain Omega-3 oils can be met by the consumption of many forms of seafood. Further, many seafood species can also be considered as rich sources of selenium, for example, and the NRVs for zinc and copper can be met by regular consumption of shellfish, like Oysters, Crabs, etcetera.

“However, there are still many gaps in our knowledge of the composition of seafood and this should be taken into account when referring to individual seafood species in relation to NRVs.”

Dr Somerset said his study had provided a number of conclusions:

• fish and other seafood are clearly a viable source of dietary long chain Omega-3 oils;
• Australian consumers can meet the NRVs for long chain Omega-3 oils entirely from the consumption of certain species of fish and other seafood without the necessity of consuming either Omega-3 supplements or foods artificially fortified with Omega-3 oils;
• feasible levels of consumption of fish and other seafood can meet the NRVs for certain other nutrients, such as selenium, zinc, copper, iodine and Vitamin B12;
• there are substantial gaps in species-specific information on the composition of fish and
• other seafood, especially in critical nutrients such as zinc, selenium, iodine and copper; and fish and other seafood are a major source of protein in the Australian diet.

Dr Somerset recommended that the seafood industry:

• advocate the inclusion of identification of specific fish species in the next Australian National Nutrition Survey (which is currently under development by the Federal Government);
• develop species-specific compositional information on fish and other seafood, especially for key nutrients such as zinc, selenium, iodine and copper;
• consider a focus on fish and other seafood as an important Iodine source in view of decreased consumption of iodised salt and progressively decreasing iodine content in dairy foods; and
• recommend consumers eat a wide variety of fish and other seafood species.

FURTHER INFORMATION: Dr Shawn Somerset 0407 642 872

Notes

• Dr Shawn Somerset is a Senior Lecturer in Human Nutrition within the Nutrition Unit, School of Health Sciences, Griffith University. He is a qualified dietitian, with a PhD from the University of Queensland and a Postgraduate Diploma in Nutrition & Dietetics from the University of Sydney. Previously, he has worked in the Queensland Departments of Health and Primary Industries & Fisheries, and has worked as a consultant to food industry in Australia and France. His major interests are food system analysis, nutrition-industry inter-sectoral collaboration and liaison, and coronary heart disease prevention.
• The Australian Government’s National Health & Medical Research Council (NHMRC) is Australia's peak body for supporting health and medical research; for developing health advice for the Australian community, health professionals and governments; and for providing advice on ethical behaviour in health care and in the conduct of health and medical research.
• Seafood the Good Food outlines the oil content and composition of 189 Australian seafood species. Each species page lists the common name, scientific name and an image. There is a summary box of oils, oil class and fatty acids, as well as fatty acid nomenclature and portion. A second publication, Seafood the Good Food II, expands on the first volume by examining factors that may influence the good oils that are present in seafood including how seafood is produced and how it is prepared for consumption. It also outlines the oil content and composition of an additional 79 seafood species not covered in Volume I. Both books are available on the website of Seafood Services Australia: http://www.seafood.net.au

  Issued: Thu Aug 7 17:23:00 EST

  Reference-id: SSANEWS0238

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