Omega 3 fatty acids also known as n-3 have a carbon to carbon double bond in the n-3 position hence their name. They are considered to be essential nutrients and need to be obtained from food. Good sources include, oily fish, enriched eggs, lamb feed on grass, flax and walnuts.
Scientists became interested in these in the 1970’s when it was discovered that people from Greenland ate a lot of seafood and had very low rates of heart disease. Since then many research studies have been completed and will be continued to be done.
Here is a summary of the research thus far:
Cardiovascular disease
- Studies show evidence of a positive effect of fish oil intake on cardiovascular disease. In patients with heart disease those that had a higher level of DHA and EPA (omega 3) had a reduction in arrhythmias and fatal heart disease. Also in post menopausal woman weekly fish consumption is associated with a slower progression of atherosclerosis.
- Multiple clinical trials have shown that omega 3 intake or supplementation is able to significantly decrease blood triglyceride levels, thus in turn lowering the risk of heart disease.
- Epidemiological studies have shown that eating fatty fish such as salmon, mackerel, trout, tuna and sardines twice a week is associated with a 30-40% decrease in cardiac events.
Chronic Obstructive Pulmonary Disease
- There are a few studies that have shown benefit in COPD (Chronic obstructive pulmonary disease) but more research is needed.
Cancer
- In the case of improving outcomes and increasing lean body mass in cancer patients, the research is inconclusive.
Conclusion
- At the present time the focus of improving our intake of fatty fish or omega 3 from plant sources such as flax seed is to disease the risk of heart disease.
Recommended Intake
- Enjoy fatty fish twice a week.
Reference:
- The American Dietetic Associations Evidence Analysis Library
By Rebecca Subbiah RD, LDN