Omega-3s are a type of polyunsaturated fat and is an essential nutrients just like the vitamins and minerals, as our body cannot make them and they play many critical roles, it is essential to include Omega-3s in our diet.
The Omega-3 (called ALA) found in plant sourced foods such as canola oil, linseeds and walnuts needs to be converted by the body to the long chain Omega-3s to be used effectively. Unfortunately this conversion is very inefficient so it is desirable to include long chain Omega-3s in the diet as well. These are found in oily fish, other fish and seafood and to a lesser extent in meats and eggs. Foods enriched with long chain Omega-3s are beginning to appear in supermarkets. Supplements of fish oil are rich in long chain Omega-3s.
Long chain Omega-3s are used effectively in the body. DHA is a major building block of the brain. The retina in the eye is very concentrated in DHA. Other vital organs such as the heart are rich in long chain Omega-3s. Both EPA and DHA are transformed to other active substances in the body which have anti-inflammatory and protective roles. It is much more difficult to ensure enough long chain Omega-3s are in the diet as so few foods contain these essential nutrients. The shorter chain Omega-3, alpha-linolenic acid or ALA, is very poorly converted in the body to the long chain Omega-3s.
Why are long chain Omega-3s important?
- These are vital nutrients required by every cell in the body
- Omega-3 DHA is a major building block of the cells in the brain and retina so it is crucial for brain growth and visual development
- Long chain Omega-3 DHA is important for the signalling processes in the brain and nervous system
- The long chain Omega-3s DHA and EPA form hormone-like substances which help reduce inflammation, increase flexibility of blood vessels and help blood flow
- The long chain Omega-3s DHA and EPA help reduce the risk of a heart attack
- Scientific research continues to identify important roles for long chain Omega-3s, including the role of DPA another type of long chain Omega-3.
Whilst fruits, vegetables and cereal grains make important contributions to a healthy diet, they do not supply long chain Omega-3s.
To prevent a deficiency of long chain Omega-3s health authorities recommend 90mg/day for women and 160mg/day for men. However, to optimise diets for lowering chronic disease risk a much higher amount is recommended:
- For women 430mg per day
- For men 610mg per day
For some health conditions (such as arthritis and high blood triglyceride levels) doctors recommend higher intakes and fish oil supplements are required.
Most people have very little long chain Omega-3s in their diet because it is found in so few foods - in fact, most New Zealanders and Australians consume less than a quarter of the optimal recommended intake. Those who regularly consume fish and seafood (at least twice a week) and who choose food varieties enriched with long chain Omega-3s may reach their target intake. Oily fish such as Salmon is a high source of natural Omega-3s.