Health effects of consuming 2 portions per week of Scottish farmed salmon raised on different feeding regimes Baukje de Roos
Sustainable sources of fish as food PROGRAMME Aquaculture has the potential to take the pressure off wild fish stocks whilst meeting the dietary needs of the population for omega 3 fatty acids and other key nutrients such as vitamin D. Reductions in fish stocks and catch quotas, in addition to sustainability considerations, mean that farmed fish may have to be raised on vegetable oils for example but this may reduce the omega 3 content and may affect the content of other nutrients. Fish are an important component of the diet and there is a need to understand the effect of pressures from sustainability on methods of production and the health giving properties of fish. We have now been commissioned by the Scottish Government s Rural and Environment Science and Analytical Services Division (RESAS) to do research on the health effects of Scottish farmed fish fed different feeding regimes in the Scottish population, and assess how differential effects in measured health outcomes could be related to fish composition.
Health properties of fish Omega-3 fatty acids (EPA, DHA) Vitamin D Other micronutrients (selenium, zinc, iron) Protects against stroke and lowers the risk of mortality from coronary heart disease Essential for the growth and maintenance of healthy bones Various functions
Cardiovascular disease Cardiovascular disease is a primary cause of premature death worldwide (in Europe accounting for 48% of all deaths) Associated health care ramifications from cardiovascular disease cost the EU economy 192 billion euros a year. Moreover, the observed decline in cardiovascular disease since the 1980s has slowed due to the increasing incidence of major risk factors like obesity, hyperlipidaemia and diabetes mellitus. Improving diet and lifestyle is a critical component of the strategy for cardiovascular disease risk reduction in the population. Allender S et al. European cardiovascular disease statistics. 2008
Main preventable causes of death Danaei G et al. PLoS Med 2009; 28;6:e1000058
Beneficial effects from fish intake on cardiovascular disease Mozaffarian D and Rimm EB JAMA. 2006;296:1885-1899
Current dietary recommendations UNITED KINGDOM: 1994: UK Committee on Medical Aspects of Food Policy (COMA) 2004: Scientific Advisory Committee on Nutrition (SACN) People are recommended to eat at least two portions (with a portion being 140 g) of fish per week, one of which should be oily fish Two portions of fish per week, one white and one oily, provide approximately 0.45 grams per day of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) ON AN INTERNATIONAL LEVEL, IN MOST WESTERN COUNTRIES: Status quo: 0.1-0.2 grams per day Prevention of cardiovascular disease: 0.4 0.6 grams per day Treatment of patients with cardiovascular disease: 1 gram per day Treatment of hypertriglyceridaemia: 2-4 grams per day
Commonly consumed oily and white fish Type of fish EPA (g/100g) DHA (g/100g) LC n-3 PUFA (g/100g) OILY FISH Fresh salmon 1.2 1.3 2.70 Pickled, smoked/canned sardines and pilchard 1.17 1.20 2.60 Kipper 1.15 1.34 2.49 Fresh mackerel 0.71 1.10 1.93 Canned sardines 0.55 0.86 1.57 Canned and smoked salmon 0.55 0.85 1.54 Fresh tuna 0.3 1.1 1.50 Herring 0.51 0.69 1.31 Fresh trout 0.23 0.83 1.15 WHITE FISH Canned tuna 0.06 0.27 0.37 Fresh plaid and whiting 0.16 0.10 0.30 Fresh cod 0.08 0.16 0.25 Fresh haddock 0.05 0.10 0.16 Fresh sole 0.00 0.00 0.10 2004. London, Scientific Advisory Committee on Nutrition
Fish: an important dietary source of vitamin D Product Vitamin D (mg/100 gram) Raw Herring 19.0 Canned sardines in brine 4.6 Canned sardines in oil 5.0 Raw Salmon 5.9 Canned Salmon 9.2 Raw Mackerel 8.2 Smoked Mackerel 8.0 Product Vitamin D (mg/100 gram) Salmon - fresh and wild caught 15-25 Salmon - fresh farmed 2.5-6.3 The Composition of Food. London: Food Standards Agency, 2002 Food rich in vitamin D [online]. Nature Systems. 2010. 7-5-2012
FISH DISH STUDY FIsh for a Sustainable Healthy Diet In Scottish Households (FISH DISH) Study In a human intervention study we will investigate the health effects of consuming two portions of oily fish (Scottish farmed salmon) per week (current UK recommendation) using fish raised on different feeding regimes.
Dietary interventions - farmed salmon For the study they will grow two different types of salmon between April 2012 and January 2013 on feeds that differ in their omega-3 levels: HPUFA: high EPA/DHA levels in feed and in salmon fillets ~15% of total feed fatty acids, equal to wild salmon SPUFA: sustainable levels of EPA/DHA in feed and in salmon fillets ~6-8% of total feed fatty acids, similar to most Norwegian farmed salmon
Dietary interventions - provision of LC n-3 PUFA Salmon diet Salmon fillet fat LC n-3 PUFA LC n-3 PUFA LC n-3 PUFA (% of total fat) (% of total fat) (per 150g portion) (intake/week) (intake/day) 25% EPA/DHA ~28% EPA/DHA 6.30 g 12.60 g 1.80 g 20% EPA/DHA ~22% EPA/DHA 4.95 g 9.90 g 1.47 g HPUFA SPUFA 15% EPA/DHA 17% EPA/DHA 3.83 g 7.66 g 1.09 g 10% EPA/DHA 12% EPA/DHA 2.70 g 5.40 g 0.77 g 5% EPA/DHA 6% EPA/DHA 1.35 g 2.70 g 0.39 g Recommendation: 0.5 g EPA+DHA per day
TIMELINE October 2012: Start volunteer recruitment February 2013: Start human intervention study November 2013: Finish human intervention study Start sample analysis Summer 2014: Publication of results
Main health outcomes Omega-3 Index Cardiovascular risk markers (blood lipids, blood pressure, bleeding time) Markers of insulin sensitivity Markers of inflammation and oxidative stress Markers of micronutrient availability (vitamin D, selenium, iodine) Markers of gut health Markers of genetic health
Acknowledgements