Omega 3

by | Nutrition, Supplements

Omega-3 fatty acids are essential polyunsaturated fatty acids. This means that you need to get them through the diet.

They play a role in the suppression of inflammation in the body, in the development of the brain and the nervous system, and have also found new uses in sports nutrition. There are hypotheses that they could help build muscle, but mainly they have a use in reducing the negative effects from concussions that occur in contact sports or headers in football.

Forms and functions of omega 3

  • Dilate blood vessels
  • Reduce inflammatory processes
  • Prevent blood clotting
  • Reduce pain
  • Dilate the airways
  • Support the immune system

Increased intake of omega-3 fatty acids is mainly associated with the prevention of cardiovascular disease.

A Cochrane meta-analysis of 78 randomised controlled trials conducted in 2020 found evidence of low and moderate certainty that higher (compared to lower) intakes of omega-3 EPA and DHA (from supplements or food) in adults at risk of cardiovascular disease modestly reduced the risk of death from cardiovascular disease, death from coronary heart disease, and coronary heart disease events. [12]

Omega-3s may improve cardiovascular health by reducing inflammation and oxidative stress and preventing plaque formation, thereby reducing the risk of atherosclerosis (hardening and narrowing of the arteries).

Omega 3 forms

There are 3 main forms of Omega 3: ALA, EPA and DHA.

ALA is the basic form of Omega 3 that plays a role in cellular energy metabolism, The body can use ALA and convert it into EPA and DHA. It is found in vegetable fats, especially flaxseeds.

EPAs prevent blood clotting, reduce triglyceride levels in the blood, and can reduce swelling and pain.

DHAs are mainly involved in children’s brain development.

EPA and DHA are mainly found in fish and seafood.

Is the conversion of ALA to DHA sufficient?

It is commonly estimated that 5% to 10% of ALA is converted to EPA, but less than 2% to 5% is converted to DHA. Even if we lack a direct source of EPA and DHA in our diet, it is possible, at least in theory, to take in enough ALA and for the body to make enough EPA and DHA.

There is also evidence in rats that DHA synthesized from ALA can meet the brain’s DHA requirements, because animals fed ALA alone have brain DHA concentrations similar to those of animals fed DHA, and the brain DHA requirement in humans has been estimated to be only 2.4-3.8 mg/day. [1]

There are also human studies that show that the synthesis of ALA to DHA may be sufficient for the adult brain. [2]

But there are factors that affect the conversion of ALA to DHA.


  • Omega 3 and 6 in foods
  • vitamin E
  • Vit B6 and B7
  • calcium
  • energy intake

The modern diet is rich in omega 6 fatty acids which share transporters and our body prefers to absorb omega 6. If we have too much omega 6 in our diet, there is no room left for omega 3 absorption.

Are omega3 from fish oil and omega3 from flaxseed oil of equal value to the body? The short answer is no.

It is assumed that our ancestors in the Paleolithic period (at the time of evolution) consumed n-6 and n-3 in a ratio of 1-2/1

Between 1935 and 1939, the n-6/n-3 ratio was 8.4/1.

In 1985 the ratio was 10.3/1 and in other calculations even as high as 12.4/1.

Later, between 2001 and 2011, the average n-6/n-3 ratio was reported to be 15-16.7/1.

Nowadays, the estimated average ratio has increased to 20/1 in Western dietary styles

We don’t know what the ideal omega 6:omega 3 ratio is, but it’s certainly not as high as we see in current diets. [13]

Overall, adding omega 3 to the diet appears to reduce the incidence of cardiovascular disease and has little effect on reducing inflammatory processes in the body. The large effect is overall higher intake of omega 3 relative to omega 6, which is a reflection of diet and lifestyle.

Recommended amount of ALA in the life stage

according to the NIH

Birth to 12 months* 0.5 g
Children 1 to 3 years 0.7 g
Children 4 to 8 years 0.9 g
Boys 9-13 years 1.2 g
Girls 9-13 years 1.0 g
Boys 14-18 years 1.6 g
Adolescent girls 14-18 years 1.1 g
Males 1.6 g
Females 1.1 g
Pregnant teenage girls and women 1.4 g
Breastfeeding teenagers and women 1.3

Omega 3 and brain development

Brain development begins early in pregnancy and a DHA form is essential for brain development. Two problems arise here. It is difficult to reliably measure a child’s cognitive abilities and the turnover of DHA in the brain takes a long time.

That said, I will rely on studies on adults and vegans (who do not consume fish nor fish oil).

Is the conversion of ALA to DHA sufficient?

It is commonly estimated that 5% to 10% of ALA is converted to EPA, but less than 2% to 5% is converted to DHA.1 Even if we lack a direct source of EPA and DHA in our diet then, it is at least theoretically possible to ingest sufficient ALA and the body will make enough EPA and DHA.

There is also evidence in rats that DHA synthesized from ALA can meet the brain’s DHA requirements, because animals fed ALA alone have brain DHA concentrations similar to those of animals fed DHA, and the brain DHA requirement in humans has been estimated to be only 2.4-3.8 mg/day. [1] 2015

There are also human studies that show that the synthesis of ALA to DHA may be sufficient for the adult brain. [2]

However, during the sensitive phases of pregnancy, breastfeeding, infancy, and early childhood, the ALA conversion process may not keep up with the increased requirements for DHA. [3]

The needs of pregnant women and children are higher

Omega-3 fats are especially important from the third trimester to the first 18 months of life for brain, retinal, and central nervous system development. During this period, 50 to 70 milligrams of DHA per day accumulate in the developing fetus,[4] and this process continues until the 18th month of life[5] Therefore, most studies begin with supplementation during the third trimester. It is generally recommended to supplement with fish oil from the beginning of pregnancy,[6]

The way I look at it is that children’s brains are still developing and therefore DHA requirements are higher than in adults. The same is true in cases of concussion.

Omega 3 and cognitive abilities in children

Results from studies in schoolchildren in low-income countries have shown relatively convincing cognitive effects of fish oil supplementation. Studies on school children from developed countries suggest a beneficial effect of intake of omega 3 and cognitive performance, but doses and effects are inconsistent across studies.

The beneficial effects on mood and school and cognitive performance among children were when supplementing 0.4-1mg/day.

Interestingly, children using DHA supplement had a more relaxed mood.

What form?

First and foremost, focus on omega 3 food sources.

Food Serving Size % RDD
Flaxseeds crushed* 10 g 2.3g (144%)
Caviar per 1.0 tbsp (16.0g) 1g (68%)
Cod liver oil per 1.0 tbsp (4.5g) 1g (53%)
Mackerel 80.0g 4g (249%)
Herring 28.4g 1g (39%)
anchovy 28.4g 1g (37%)
tuna 85.0g 1g (88%)

Omega 3 supplements

In a 2023 meta-analysis, omega-3 fatty acid supplementation did not improve cognitive function compared to placebo in adults over 40 years of age. But higher doses showed a trend toward improvement. [8]

Should you take a supplement?

  • Do you eat omega-3 rich fish at least 3-5 days a week, or crushed flax or chia seeds at least 10g a day?
  • Do you have a low omega 3 intake.
  • You don’t eat fish and want to get insurance.
  • You are pregnant.

Fish oil is best for bioavailability and absorption and to increase the omega 3 index. In studies evaluating microalgae oil, it was found to improve the omega 3 index, while high doses of flaxseed and echium seed supplements did not improve the omega 3 index [7].

What to look out for when choosing Omega 3 supplements

Both fish and vegetable oils are susceptible to oxidation caused by heat, light and oxygen. For maximum health benefit to you, it should not be oxidized.

According to a 2017 study, nearly 50% of fish oils exceeded maximum oxidation levels. According to a later study from 2020, it was 27%. [9, 10]

According to a 2022 study of twenty omega 3 supplements that included both fish and vegetable oils, all supplements tested were compliant – they did not exceed the maximum allowable oxidation level. [11]

Not all forms of fish oil are the same:

  • Make sure the product you’re using contains >90% triglycerides, as fish oils can contain 50-90%.
  • If the supplement information doesn’t list the triglyceride form, it is probably an ethyl ester.

How much?

For all goals, the current recommendation is to take 2-4g of omega 3 per day, primarily from food.

  • 100-200 mg for pregnant women
  • A daily DHA supplement of 100 mg is recommended for all children, including vegans, aged 6 months to 3 years. [3]
  • 100-200mg children after 2 years of age
  • For adults on a vegan diet, supplementation with 250mg of DHA and 150mg of EPA is recommended.

10g of crushed flaxseed should provide enough ALA for conversion to EPA and DHA, but if you want to be on the safe side, I recommend using a nutritional supplement, e.g.

  • Opti3
  • Myprotein
  • Veganicity


  1. Domenichiello AF, Kitson AP, Bazinet RP. Is docosahexaenoic acid synthesis from α-linolenic acid sufficient to supply the adult brain?. Prog Lipid Res. 2015;59:54-66. doi:10.1016/j.plipres.2015.04.002
  2. Sutter DO, Bender N. Nutrient status and growth in vegan children. Nutr Res. 2021;91:13-25. doi:10.1016/j.nutres.2021.04.005
  3. Baroni L, Goggi S, Battaglino R, et al. Vegan Nutrition for Mothers and Children: Practical Tools for Healthcare Providers. Nutrients. 2018;11(1):5. Published 2018 Dec 20. doi:10.3390/nu11010005
  4. Clandinin MT, Chappell JE, Heim T, Swyer PR, Chance GW. Fatty acid utilization in perinatal de novo synthesis of tissues. Early Hum Dev. 1981;5(4):355-366. doi:10.1016/0378-3782(81)90016-5
  5. Denomme J, Stark KD, Holub BJ. Directly quantitated dietary (n-3) fatty acid intakes of pregnant Canadian women are lower than current dietary recommendations. J Nutr. 2005;135(2):206-211. doi:10.1093/jn/135.2.206
  6. Greenberg JA, Bell SJ, Ausdal WV. Omega-3 Fatty Acid supplementation during pregnancy. Rev Obstet Gynecol. 2008;1(4):162-169.
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  8. Suh SW, Lim E, Burm SY, et al. The influence of n-3 polyunsaturated fatty acids on cognitive function in individuals without dementia: a systematic review and dose-response meta-analysis. BMC Med. 2024;22(1):109. Published 2024 Mar 12. doi:10.1186/s12916-024-03296-0
  9. Bannenberg G, Mallon C, Edwards H, et al. Omega-3 Long-Chain Polyunsaturated Fatty Acid Content and Oxidation State of Fish Oil Supplements in New Zealand. Sci Rep. 2017;7(1):1488. Published 2017 May 3. doi:10.1038/s41598-017-01470-4
  10. Jairoun AA, Shahwan M, Zyoud SH. Fish oil supplements, oxidative status, and compliance behaviour: Regulatory challenges and opportunities. PLoS One. 2020;15(12):e0244688. Published 2020 Dec 31. doi:10.1371/journal.pone.0244688
  11. Pasini F, Gómez-Caravaca AM, Blasco T, Cvejić J, Caboni MF, Verardo V. Assessment of Lipid Quality in Commercial Omega-3 Supplements Sold in the French Market. Biomolecules. 2022;12(10):1361. Published 2022 Sep 23. doi:10.3390/biom12101361
  12. Bernasconi AA, Wiest MM, Lavie CJ, Milani RV, Laukkanen JA. Effect of Omega-3 Dosage on Cardiovascular Outcomes: An Updated Meta-Analysis and Meta-Regression of Interventional Trials. Mayo Clin Proc. 2021;96(2):304-313. doi:10.1016/j.mayocp.2020.08.034
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  15. Lauritzen L, Brambilla P, Mazzocchi A, Harsløf LB, Ciappolino V, Agostoni C. DHA Effects in Brain Development and Function. Nutrients. 2016;8(1):6. Published 2016 Jan 4. doi:10.3390/nu8010006