Fish is very good for us, and the fish oil itself may prevent chronic diseases such as heart disease. New research has now shown that this type of omega 3 fat is necessary for growth and development, cognitive function and may even impact our behavior.

Research has found that omega 3’s in fish oil such as DHA (docosahexaenoic acid) is needed to support optimal health of the baby during pregnancy. DHA is also necessary for healthy growth of the infant, but also necessary for mental and psychomotor development. The well known Oxford Durham study found that DHA plus EPA (eicosapentaenoic acid), the other omega-3 fat from fish, when consumed regularly improved spelling and reading in children, 5 to 12 years of age. It also found behavioral improvements with the addition of these omega-3s.

DHA and EPA are long chain omega-3 fats and are different from the essential omega-3 fats found in flax and canola oil. These types of omega-3s we can only get from marine foods. In 2002 the US Food and Nutrition Board set target intakes for DHA and EPA omega-3 fats. In Australia and Britain, government experts advise healthy people to eat enough fish to get 0.4 to 0 .6 grams a day of the omega-3 fats, DHA and EPA. The American Heart Association even advises people who have heart disease to take a daily supplement with 1 gram of DHA plus EPA. The Canadian and US government health however have no specific recommendations to date. Currently, Health Canada recommends healthy people eat fish at least twice a week.

What we know

Many studies report people who eat more fish are less likely to die of a heart attack than those who eat less fish. In 2004, 13 studies were compared that looked at over 220,000 people for an average of 12 years and found those who ate fish at least five times a week had a 40 percent lower risk of death from heart disease. The strongest clinical support for its cardiovascular protection is the Italian GISSI study, which showed a 40 percent reduction in sudden death heart attack with those supplemented with fish oil (EPA/DHA). Current research has also found that fish oil lowers triglycerides in 18 months, and decreases stroke rate as fish consumption increases.

What we are learning

The retina is made of DHA and it may impact the health of the macula, the centre of the retina. As we age, Age Related Macular Degeneration (ARMD) is the leading cause of blindness in Canadians over age 65. In 2007, the largest eye disease study of its kind was re-evaluated and it was found that people who ate fish at least twice a week had almost a 50 per cent reduction in the risk of ARMD compared to people who never ate fish.

DHA may have a function in brain health. DHA is in large concentrations in the brain and found in cell membranes. DHA may affect how cells communicate with each other and how cell components interact. Recently in the American Journal of Clinical Nutrition a study showed that with a higher omega 3 intake, from fish, reduced the risk of decline in verbal fluency in elderly men over a 5 year period. Another recent study in Neurology, found that a diet rich in fish, fruits, and vegetables could contribute to the decrease risk of dementia and Alzheimer’s disease in older persons whereas a higher consumption of omega 6 rich oils could exert detrimental effects.

In 2005 research found that healthy subject’s with an average age of 33, when they consumed 800 mg DHA plus EPA for 35 days showed increased vigor and decreased anger, anxiety, fatigue, and depression.

The Bottom Line

Eat more fish. Eat fatty fish like salmon at least twice a week to supply 0.5 to 1 gram a day of DHA plus EPA. Encourage your children to eat fish at least once a week.

If you take fish oil supplements, read the label for exact content of DHA and EPA. Also, look at the source of the fish oil. Fish oils from anchovy or sardines contain fewer toxins.