Fish eaters run lower risk of heart attack – despite some mercury content

September 24, 2012

Eat fish, but avoid fish with the most pollutants. This is the conclusion drawn by a group of researchers at Umeå University in Sweden after having weighed the risks of mercury content against the advantages of healthful fatty acids. The work was done as part of an international collaborative effort.

is healthful food, and several studies have shown that people who eat fish have a lower risk of cardiovascular diseases than those who eat very little or no fish. At the same time, some fish contain that can be hazardous to our health. One such pollutant that is suspected of increasing the risk of cardiovascular disease is methyl mercury, which is found in varying degree in different kinds of fish. If people eat fish with much pollutants, this would lead to increased risk of disease, but at the same time if people are overly cautious and eat too little fish, the risk of disease also increases.

In order to attain a better understanding of what the golden mean might be, researchers at Umeå University, in collaboration with researchers from Finland and elsewhere, examined how the risk of () is contingent on the amount of omega-3 fats and mercury from fish that people have in their body. The content was measured in blood and hair samples from people that had previously participated in health studies in northern Sweden and eastern Finland. The Swedish blood samples were from the Medical in Umeå. Those who experienced a heart attack after the health check-up were compared with those who did not.

The findings are now being published in (AJCN). It turned out that mercury was linked to increased risk, and omega-3 fatty acids to decreased risk, of having a heart attack. The increased risk from mercury was noticeable only at high levels of this environmental pollutant in the body and if the level of the protective omega-3 fatty acids was concomitantly low. In other words, what is important is the balance between healthful and hazardous substances in fish. The environmental pollutant in this study was mercury. For organic pollutants like PCB and dioxin, the problem complex is similar, but no study of this kind has yet been undertaken.

The conclusion is simple: Eat fish, but avoid fish with the most pollutants. The Swedish National Food Agency recommends that people should eat fish 2–3 times a week, but their intake of predatory fish (e.g. pike, perch, pike-perch), which contain a great deal of mercury, should be limited (see link below). This study supports that recommendation. According to a recent study from the National Food Agency, 7 of 10 Swedes eat too little fish.

Explore further: Young women may reduce heart disease risk eating fish with omega 3 fatty acids

More information: M Wennberg, U Strömberg, IA Bergdahl, JH Jansson, J Kauhanen, M Norberg, JT Salonen, S Skerfving, TP Tuomainen, B Vessby, JK Virtanen: Myocardial infarction in relation to mercury and fatty acids from fish: a risk-benefit analysis based on pooled Finnish and Swedish data in men
American Journal of Clinical Nutrition (AJCN), published ahead of print 2012. doi: 10.3945/ajcn.111.033795

Related Stories

Young women may reduce heart disease risk eating fish with omega 3 fatty acids

December 5, 2011
Young women may reduce their risk of developing cardiovascular disease simply by eating more fish rich in omega-3 fatty acids, researchers reported in Hypertension: Journal of the American Heart Association.

Omega-3 supplements no help against repeat heart trouble: review

April 9, 2012
(HealthDay) -- Taking omega-3 fatty acid supplements won't protect against repeat heart attacks, strokes or other cardiovascular problems, a new analysis indicates.

Food scientists fortify goat cheese with fish oil to deliver healthy omega-3 fatty acids

February 16, 2012
Fish oil is an underused ingredient in the food industry because of its association with a strong odor and aftertaste. A new study in the February issue of the Journal of Food Science, published by the Institute of Food Technologists, ...

Recommended for you

No evidence that widely marketed technique to treat leaky bladder/prolapse works

October 16, 2017
There is no scientific evidence that a workout widely marketed to manage the symptoms of a leaky bladder and/or womb prolapse actually works, conclude experts in an editorial published online in the British Journal of Sports ...

Ten pence restaurant chain levy on sugary drinks linked to fall in sales

October 16, 2017
The introduction of a 10 pence levy on sugar sweetened drinks across the 'Jamie's Italian' chain of restaurants in the UK was associated with a relatively large fall in sales of these beverages of between 9 and 11 per cent, ...

New exercises help athletes manage dangerous breathing disorder

October 16, 2017
A novel set of breathing techniques developed at National Jewish Health help athletes overcome vocal cord dysfunction and improve performance during high-intensity exercise. Vocal cord dysfunction, now also referred to as ...

Learning and staying in shape key to longer lifespan, study finds

October 13, 2017
People who are overweight cut their life expectancy by two months for every extra kilogramme of weight they carry, research suggests.

Blueberries may improve attention in children following double-blind trial

October 13, 2017
Primary school children could show better attention by consuming flavonoid-rich blueberries, following a study conducted by the University of Reading.

Menopause linked to changes in brain energy use

October 13, 2017
Researchers from Weill Cornell Medicine and the University of Arizona Health Sciences have found that women's brains use less energy during the menopause. The reduction in energy use by the brain was found to be similar to ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.