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

'Man flu' may be real

December 11, 2017
The much-debated phenomenon of "man flu" may have some basis in fact, suggests an article published in the Christmas issue of The BMJ.

Full moon linked to increased risk of fatal motorcycle crashes

December 11, 2017
The full moon is associated with an increased risk of fatal motorcycle crashes in the United States, the United Kingdom, Canada and Australia, finds a study in the Christmas issue of The BMJ.

Social media trends can predict tipping points in vaccine scares

December 11, 2017
Analyzing trends on Twitter and Google can help predict vaccine scares that can lead to disease outbreaks, according to a study from the University of Waterloo.

Study suggests being proud may protect against falls in older people

December 11, 2017
Contrary to the old saying "pride comes before a fall", the opposite appears to be true, according to a study published in the Christmas issue of The BMJ.

Peppa Pig may encourage inappropriate use of primary care services

December 11, 2017
Exposure to the children's television series Peppa Pig may be contributing to unrealistic expectations of primary care and encouraging inappropriate use of services, suggests a doctor in the Christmas issue of The BMJ.

Women's sexual orientation linked to (un)happiness about birth

December 11, 2017
Unhappiness about a pregnancy or birth has been associated with negative health outcomes for mothers and babies. Yet, unhappiness about a pregnancy or birth has been understudied, particularly among sexual minority (non-heterosexual) ...

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.