The Benefits of Fish Oil and Omega 3. The role of Fatty acids, EPA, DHA & ALA

The Benefits of Fish Oil and Omega 3. The role of Fatty acids, EPA, DHA & ALA

Introduction – Omega 3 fatty acids

Fish oil Omega-3 fatty acids are a major component of polyunsaturated fatty acids (PUFA) from fish oil. Omega-3 has many health benefits. It has been found that a daily intake of docosahexaenoic acid (DHA) up to 0.5–0.7 g decreases the chances of Coronary heart disease (Kris-Etherton, Harris and Appel, 2002).

Omega-3 supplements can be taken if our everyday food is deficient in omega-3.

Omega-3 fatty acids also has beneficial effects in rheumatoid arthritis, inflammatory diseases such as asthma (Reisman et al. (2006), cystic fibrosis and bowel diseases. A high DHA content in the body can help decrease the risk of Alzheimer’s disease.

tuna oil supplement


Types of fat; Unsaturated fats and Saturated fats


The body requires fat to stay healthy and fat is an important source of essential fatty acids that cannot be produced by the body. Fats play an important role to help absorb the fat-soluble vitamins into the body. Fats can be broken down into either saturated fats or unsaturated fats.

Saturated fats can be found in many foods including meat and dairy products as well as plant sources like coconut oil. Cholesterol which is a fatty substance found in the blood is also linked to saturated fats.

Too much saturated fats can raise LDL cholesterol which can then increase the risk of heart disease and stroke.

Unsaturated fat, on the other hand, can help reduce cholesterol levels in the blood. These can be sourced mainly from fish and some plants and can be classed as either monounsaturated or polyunsaturated fats.


What is ALA

Alpha-linolenic acid (ALA) is the parent of all fatty acids in the omega 3 family.

What is EPA and DHA

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can be described as long chain fats that are found primarily in fish and fish oil. They are classed polyunsaturated fats and offer huge health benefits. They can be described as the most potent and beneficial of the omega 3 fats and these are mostly obtained from seafood.

Omega 3: Benefits of Omega 3

Omega 3 which was originally referred to as Vitamin F was discovered somewhere around 1920. Since then, lots and lots of research has gone into it to understand the key benefits of omega 3 on human health. We have different types of omega 3 fatty acids which can depend on the source. For example, omega 3 fat from plant sources such as flaxseed oil or flax meal differs from omega 3 fat from fish. These different types of omega 3 fat play different roles in the body and it is important we maintain a good balance of all the different types of omega 3 fat.


The types of unsaturated fats in food can be classed as either polyunsaturated or monounsaturated fats. Omega 3 and Omega 6 are classed as polyunsaturated and Omega 9 fats are classed as monounsaturated.  As previously stated, these polyunsaturated fats can either come from plant or animal sources.


Some of the important activities these omega 3 fats play in the body include

  1. Turning genes on and off – They help regulate the genes in our body which includes the brain
  2. Anti-inflammatory -Omega 3 plays a key role in fighting inflammation and infection


Other key roles that are played by omega 3 fatty acids are

  1. Brain – DHA contributes to the maintenance of normal brain function. It does this by helping to make and regulating important chemicals in the brain. The beneficial effect is obtained with a daily intake of 250 mg of DHA
  2. Vision – DHA contributes to the maintenance of normal vision. Omega 3 is required for eyesight development from birth to end of life. The beneficial effect is obtained with a daily intake of 250 mg of DHA.
  3. Heart health – EPA and DHA contribute to the normal function of the heart. It supports the heart in maintaining a steady and healthy beat which may help prevent some cardiovascular-related diseases. The beneficial effect is obtained with a daily intake of 250 mg of EPA and DHA.
  4. Healthy joints – Together with calcium, omega 3 helps support healthy joints and may prevent the destruction of cartilage and joint pain.

omega fish oil supplement for heart


Omega 3 fatty acids have also been known to have a positive effect in preventing illness and conditions like

  1. Alzheimer’s
  2. Stroke (Heart attacks)
  3. Inflammation

There is also inconclusive evidence on how it may be useful in treating

  1. Depression
  2. Dyslexia
  3. Arthritis
  4. Cystic fibrosis

Evidence of the benefits of omega 3 fish oil

Omega 3 fish oil supplements are among the commonest supplements used by adults. Aside from being a good source of vitamin A and D, what makes this omega 3 so popular?

Omega 3 fatty acids are important for fetal development, and supplementation during pregnancy has also been linked to decreased immune responses in infants. 

Another benefit of omega 3 is the role it plays in improving cardiovascular health. Studies have shown that fish-eating communities such as Japan and the Eskimos in Greenland have low rates of heart diseases compared to other regions. They also tend to have lower rates of conditions such as arthritis that are connected to inflammation in the body.

Below is a table highlighting the key benefits of omega 3 that is supported by scientific research.


Benefits of Omega 3 Fish Oil AuthorTitleComment
CardiovascularBulliyya 2002Influence of fish consumption on the distribution of serum cholesterol in lipoprotein fractions: comparative study among fish‐consuming and non‐fish‐consuming populationsThe intake of fish may have substantial implications for public health and health economy by decreasing the risk of cardiovascular disease. However, more studies are warranted to better define the mechanisms of cardioprotection by dietary fish and fish oils.
Dewailly et al 2003Fish Consumption and Blood Lipids in Three Ethnic Groups of Québec (Canada)Our results indicate that increased consumption of fish as a source of n-3 fatty acids is beneficially associated with levels of HDL cholesterol and triacylglycerols
Hu et al 2002Fish and Omega-3 Fatty Acid Intake and Risk of Coronary Heart Disease in WomenAmong women, higher consumption of fish and omega-3 fatty acids is associated with a lower risk of coronary heart disease, particularly coronary heart disease deaths
Oomen et al 2000Fish Consumption and Coronary Heart Disease Mortality in Finland, Italy, and the Netherlands The data suggest that especially fatty fish is protective against coronary heart disease mortality
Gissi 1999Dietary supplementation with n-3 polyunsaturated fatty acids and vitamin E after myocardial infarction: results of the GISSI-Prevenzione trial.Dietary supplementation with n-3 PUFA led to a clinically important and statistically significant benefit.
Inflammatory (RA)Darlington and Stone 2001Antioxidants and fatty acids in the amelioration of rheumatoid arthritis and related disordersOverall, there is a growing scientific rationale for the use of dietary supplements as adjuncts in the treatment of inflammatory disorders such as rheumatoid arthritis and osteoarthritis.
Cleland et al 2003The role of fish oils in the treatment of rheumatoid arthritisBeneficial anti-inflammatory effects of dietary fish oils have been demonstrated in randomised, double-blind, placebo-controlled trials in rheumatoid arthritis (RA)
Fortin et al 1995Validation of a meta-analysis: the effects of fish oil in rheumatoid arthritisUse of fish oil improved the number of tender joints and duration of morning stiffness at 3 months
Brain healthYehuda et al 1999Essential fatty acids are mediators of brain biochemistry and cognitive functionsFatty acids exert a controlling function in the modulation of neuronal membrane fluidity
Helland et al 2003Maternal supplementation with very-long-chain n-3 fatty acids during pregnancy and lactation augments children’s IQ at 4 years of age.Maternal intake of very-long-chain n-3 PUFAs during pregnancy and lactation may be favorable for later mental development of children.
Mental healthRichardson & Ross 2000Fatty acid metabolism in neurodevelopmental disorder: a new perspective on associations between attention-deficit/hyperactivity disorder, dyslexia, dyspraxia and the autistic spectrum.
(Behaviour disorders)Stevens et al 1995Essential fatty acid metabolism in boys with attention-deficit hyperactivity disorderThe present study found that 53 subjects with ADHD had significantly lower concentrations of key fatty acids in the plasma polar lipids and in red blood cell total lipids than did the 43 control subjects.
Depression & BipolarHibbeln 1998Fish consumption and major depression
Maes et al 1999Lowered omega3 polyunsaturated fatty acids in serum phospholipids and cholesteryl esters of depressed patientsThe results show that, in major depression, there is a deficiency of omega3 PUFAs
Nemet et al 2002Addition of omega-3 fatty acid to maintenance medication treatment for recurrent unipolar depressive disorderHighly significant benefits of the addition of the omega-3 fatty acid compared with placebo were found by week 3 of treatment.





What are good dietary sources for Omega 3


There are different food sources for omega 3. Some good plant-based food sources for omega 3 include walnuts, green leafy vegetables, and flaxseed. Marine based food sources for omega 3 include fish oil, fatty fish and seaweed.

For omega 6 fats, meat and poultry are good animal food sources whereas sunflower, soybean, and corn are examples of good plant-based source for omega 6

Omega 9 which is a monounsaturated fat can be obtained from avocado, peanuts, olive oil, and almonds.

good sources of fish oil

The table below provides some examples of good fish sources for omega 3 fatty acids

 EPADHAEPA + DHAServings per week to meet 500 mg/day recommendation
Salmon (Pink)1853395246.5
Salmon (wild atlantic)349121515642
Sea Bass1754736485.5
Bluefin Tuna30997012793
Canned Tuna (water)4019023015
Mackerel (Atlantic)4285941022


Source: Raatz, Susan K – Fish and fish oil in health and disease prevention-Academic Press (2016)


It is estimated that just a third of UK adults consume oily fish with an average intake of one small portion per week. It is therefore important to consider fish oil supplementation as an inexpensive option of meeting a recommended daily EPA and DHA intake.

oily fish supplement


Choosing Fish Oil or Omega 3 supplement

The best sources of omega 3is from seafood. The American Heart Association recommends eating 2 servings of fish (particularly fatty fish) per week. Salmon, mackerel, herring, sardines and albacore tuna are some examples of fatty fish that are high in omega 3. If you are not consuming this regularly, it may be worth supplementing your diet with high strength omega-3 supplements.


What is the best omega 3 supplement? With the endless number of options on the market, how do you choose the best omega 3 supplement for use? How do you pick the better option from cod-liver oil supplements, salmon oil supplements, CLA supplements, Omega 3 6 9 supplements etc.?

best fish oil supplement


Some omega 3 supplements on the market claim they contain added omega 3 and omega 9 fat from various sources. Most often, these claims are untrue and will not contain EPA or DHA from the specialty plant sources they mention. Omega 6 and omega 9 may not be required through additional supplementation as we typically get enough from a well-balanced diet.


An ideal option is to get these omega 3 fats from fish oil supplements as they are mostly more effective. This is also because EPA and DHA can only be found in fish oil omega 3 supplements.


Another good option is krill oil supplements. Krill are small crustaceans of the order Euphausiacea and are found in all the world’s oceans. Krill oil supplements are known to contain both DHA and EPA.

In choosing the best fish oil omega 3 supplement;

  1. It is also worth considering the number of capsules you are willing to swallow per day and the decision should not be solely driven by cost.
  2. Care should be taken to help separate fact from marketing hype as the quality of some unknown or “low” brands are equal to that of the more expensive known brands.
  3. It is also important to check the label to know the ingredients and to ensure that the expiry date is far enough in the future to allow enough time for the product to be used.


The recommended dietary allowance for omega 3s is 1600mg for males and 1100mg for females to support overall health. This may be higher in some special circumstances but should be under the direction of a qualified medical expert. A research paper stated that the evidence base supports a dietary recommendation of approximately 500mg per day of EPA and DHA for cardiovascular disease risk reduction and that for the treatment of existing cardiovascular disease, 1000mg per day. This appears to be in line with the recommendation from international health agencies.


One capsule of standard fish oil omega 3 supplements should contain at least 100mg of EPA and DHA and this may be higher depending on concentration, size and the brand of the product. Typically, one daily capsule will provide about 1000mg to 3000mg of EPA and DHA per week. This can be compared to

1300mg of EPA and DHA in 100g of herring

1930mg of EPA and DHA in 100g of mackerel

25mg of EPA and DHA in a 100g serving of cod


This presents a strong case for taking omega 3 fatty acids supplements. It is important to note that the manufacturer’s recommended dose for omega 3 supplements should not be exceeded.


Given the health benefits of omega 3 fatty acids (EPA/DHA) in cardiovascular, brain health, inflammatory and mental health, coupled with the fact that majority of us do not consume enough oily fish per week, it may be worth considering fish oil omega 3 supplements as an inexpensive way of filling any nutritional gaps we may have.





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