Seafood and Health Conference Published: 04 December, 2008
A one day conference on seafood and health being held in Fishmongers Hall, London on 28th January 2009 promises to bring forward new thinking on a range of dietary issues in which seafood can be beneficial.
Leading speakers from the UK, US, France and Ireland will present new evidence that seafood has much wider benefits than just the omega-3 content, on which so much emphasis has been placed to date. Whilst omega-3 remains a key factor, because seafood and freshwater fish are the only direct sources of these essential long fatty acids, the low level of other fats, saturated fats and omega-6s, which are too abundant in the western diet, need to be factored into the debate. There is also some evidence that whitefish, like cod, can satiate appetite at a lower level of calories than other protein foods. This could be a key factor in the obesity debate. Dr. Anna Karin Lindroos, a senior researcher at the Human Nutrition Laboratory of the Medical Research Council, based in Cambridge, will describe the current state of play in this new research area. It could change the whole emphasis of dietary advice aimed at weight loss.
In the meantime the largely mythical belief that eating foods which contain cholesterol will actually raise peoples blood cholesterol levels has now been finally dismissed by a new study at Surrey University Medical School, Guildford, carried out by a team under Dr. Bruce Griffin. In a properly controlled dietary cross-over trial, (surprisingly the first time this has been done in a realistic diet situation) a daily ration of 225 g of cold water prawns did not raise cholesterol levels in normal men. It is now accepted that only a very tiny number of people with genetic disorders that cause them to concentrate cholesterol from their food need have any concern about cholesterol in crustacean shellfish such as prawns. Even these people do not need to exclude them from their diet.
Another new study has shown that many shellfish have higher levels of heart-protecting omega-3 fatty acids than previously thought. brown crab has as much as oily fish, and oysters and mussels are not far behind. Much of the omega 3 is in the coral, for example in scallops, and in the brown meat of crab. The previously published figures appear to relate only to the white meat of these species, probably because many of the published figures are from the US, where the coral is not normally eaten. So the rich omega-3s in shellfish far outweigh any concerns about cholesterol and all the evidence suggests that seafood, including shellfish, is beneficial for heart health.
The conference will unfold the rationale behind the new thinking. Prof. Michael Crawford is well known for his explanation of the way humans evolved on a diet high in omega 3s, which are essential to the development of large healthy brains, visual acuteness and a healthy nervous system. Prof William Lands, the veteran lipid researcher who has always cast doubt on the absolute link between cholesterol and heart disease and even between saturated fat and heart disease, will explain the importance of maintaining a good omega-3 to omega-6 balance in the diet and avoiding the great excess omega-6 level now so prevalent in the western diet.
Prof. Philip Calder from Southampton University Medical School will describe some of the mechanisms by which the anti-inflammatory properties of omega 3s operate, whereas omega-6s can have opposite effects.
Two medical practitioners, Dr. Tom Gilhooly from Glasgow and Dr David Levy, a diabetes consultant, will talk about the value of omega-3s in treatment. Dr. Gilhooly offers his patients an omega-3 blood check, which may be even more important than a cholesterol check. This follows naturally from Prof. Lands explanation that when a good omega-3 balance is maintained, there is little relationship between cholesterol and heart disease.
The value of seafood as a rich source of minerals and vitamins is well known, but even here there is new evidence. Prof. Barbara Demeneix, who works at the Natural History Museum in Paris, will point out the need for a good balance of iodine and selenium in the diet and the way in which seafood naturally provides this combination. Selenium also protects the body against mercury, so many of the concerns that have been expressed about mercury in oily fish may not apply in a well balanced diet rich in a variety of seafood.
Irish dietician Sarah Keogh, who advises BIM on seafood and health and who wrote their excellent guide on this, will be presenting new ideas on the importance of vitamin D in the diet.
There are clearly a lot of new angles on the benefits of seafood in the diet, so this in a conference not to be missed.
Details are on the Fishmongers Company website www.fishhall.co.uk