Why Fish Should Be On Your Diet List?

Fish, like salmon, mackerel and albacore tuna, that high in omega-3 fatty acid is good for the heart because omega-3 fatty acid could reduce the risk of coronary heart disease. Perhaps this is why American Heart Association (AHA) advice people to eat at least 2 servings of fish a week.

Despite concerns on the impact of increased exposure to mercury in fish, Swedish researchers from Umea University in Sweden argued in their paper published in November 2010 in ‘American Journal of Clinical Nutrition’ that the benefits of consuming fish still outweigh the harmful effects of mercury. However, they also advised people to avoid eating fish high in mercury, which include perch, shark, swordfish and halibut.

More than 900 Swedish men and women took part in a study that required them to answer questionnaires about the amount of fish in their diet. Their mercury and selenium levels in red blood cells were analyzed.

While the mercury levels were generally low for Scandinavians, participants who had higher mercury level in their red blood did not have a higher risk of cardiac problems. It is possible that the protective nutrients in fish offset any harmful effect of mercury at these low levels of mercury, as explained by the researchers.

Meanwhile, the researchers admitted that relying on the participants’ memories on the amount of fish consumed could have drawbacks as this could have an impact on the results obtained. They also highlighted one finding from their study: participants who had elevated traces of selenium in their red blood cells appeared to have higher risk of sudden cardiac death.

Selenium is a trace mineral that is essential to good health but only small amounts are needed. It appears to act as an antioxidant that can reduce risk of cardiovascular disease and cancer.

Nevertheless, previous findings on effect of selenium on heart were mixed. Several studies suggested risk of heart disease and stroke might be reduced by about 40 percent by an added 100 mg per day of dietary selenium. On the other hand, a study by researchers from University of Warwick found that total cholesterol levels increased by 8 percent with an increase of 10 percent in LDL (so called bad cholesterol) in participants having more than 1.2 mol/L of selenium in their blood, leading to increase in risk of cardiovascular disease.

As such, the Swedish researchers felt that the health effect of selenium should further be probed.