A new Dutch study has failed to back up the increasingly held belief in the medical community that adding fish to one’s diet will protect significantly against heart failure.

The study sought to measure how adding fish to the diet would affect a group of 5299 subjects (41% men, mean age 67.5 years), beginning  its data collection in 1990. Specifically the researchers were looking at the role of long-chain n-3 polyunsaturated fatty acids (PUFAs), (which are found in fish) in heart disease prevention.

The subjects of the study were all deemed heart disease free at the beginning of the study. They completed a baseline study about their dietary habits, making special note of how, when and if fish was a part of their regular diet.

Their results showed that fish intake did not significantly affect the risk of developing heart disease. Relative risk was measured according to five different levels of fish consumption amongst the participants as reflected in intake of two long chain n-3 PUFAs (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]). Both of these substances had been shown in the past to have a certain cardiac benefit, having both anti inflammatory and anti arrhythmic effect. They also have some ability to lower blood triglycerides, heart rate and blood pressure.

The relative-risk (RR) of heart failure in the Maximum and minimum quintile of EPA plus DHA intake was 0.89 (95% CI, 0.69 & 0.14) after the figures were adjusted for today’s lifestyle and dietary factors, which is considered a non-significant finding.

However, as the study’s lead author Dr Marianne Geleinjse from Wageningen University is quick to point out, the findings of her study should in no way change the current recommendation that people consume at least two weekly servings of fish a week, both for their cardiovascular and their overall health. In addition to the fatty acids fish is also a good source of essential dietary components such as Vitamin D and selenium, and is a better source of protein than the more frequently consumed red meat.

The authors of this new study say that this was in fact the second study to the relationship between PUFAS and heart disease. The other study, which was undertaken over the course of 12 years, did demonstrate that the consumption of certain baked or broiled fish, especially tuna, was associated with a lower incidence of heart failure. That benefit however disappears once the fish is fried.