-Understanding Omega-3
What is Omega-3?
Omega-3s are fatty acids, i.e., the molecular constituents of lipids, in other words, fats. More precisely, omega-3s belong to the family of polyunsaturated fatty acids, compounds that are essential for the proper functioning of the body. This family is made up of omega-6 and omega-3. The precursor of all omega-3s is alpha-linolenic acid (ALA). From this, the body can synthesize all the omega-3s, some of which are qualified as essential, such as DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). It is therefore essential to have a diet sufficiently rich in omega-3 to compensate for any deficiencies.
What are the daily recommendations concerning omega 3?
Because of the importance of omega-3 fatty acids, health authorities have established daily nutritional recommendations to ensure a good supply for the body. Below are the recommendations issued by the EFSA (European Food Safety Authority) concerning omega 3:
 Alpha-linolenic acid (ALA) | |
Infants (7-11 months, male and female) | 0.5% of energy intake  |
Children (1 year, male and female)Â Â | |
Children (2 – 3 years, male and female)Â Â Â Â Â Â Â | |
Children (4 – 17 years, male and female)Â Â Â Â Â | |
Adults (18 years and older) Â Men and women (including pregnant and lactating women)Â Â Â Â Â Â Â | |
 Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) | |
Infants (7 – 11 months, male and female) | 100 mg/day DHA |
Children (1 year, male and female) | 100 mg/day DHA |
Children (2 – 3 years, male and female) | 250 mg/day DHA + EPA |
Children (4 – 17 years, male and female) | 250 mg/day DHA + EPA |
Adults (18 years and older)             Men and women      Pregnant and lactating women |  250 mg/day DHA + EPA 100 to 200 mg/day of DHA in addition to 250 mg/day of DHA + EPA |
The best food sources of omega 3
Many foods are rich in omega-3s and can easily cover the body’s needs.
Omega-3s are very present in plant-based foods. The richest oil is undoubtedly flaxseed oil (53.3 g/100g). Certain oils such as chia oil (17.8 g/100g), walnut oil (11.9 g/100g), or rapeseed oil (7.54 g/100g) are also very interesting sources of omega 3.Â
In terms of animal sources, the key foods are fatty fish such as mackerel (0.96 g/100g EPA; 1.56g/100g DHA), salmon (0.62 g/100g EPA; 0.88 g/100g DHA), red tuna (0.28 g/100g EPA; 0.89 g/100g DHA), but also oysters (0.15 g/100g EPA; 0.071 g/100g DHA).
TIP: Did you know that?
Marine waters are increasingly polluted by heavy metals such as mercury, but also by plastic microparticles. All these pollutants will accumulate in the tissues of fish. Thus, large predators such as tuna, shark, or swordfish will contain more of them than small fish present at the beginning of the food chain. It is therefore advisable to consume only certain species for greater safety. For example, for tuna, you should be sure to eat yellowfin or skipjack. Also, think of preferring small fish such as sardines, herring, and anchovies. They contain a good amount of DHA but are much less polluted than large fish.
What are the health benefits of omega 3?
Omega-3s have several health benefits recognized by European health authorities. We explain them to you below:
Contribute to eye health
Omega-3 is particularly present in the retina of the eyes. Therefore, they contribute to the maintenance of normal vision. Studies have shown that they could help reduce the risk of age-related macular degeneration by 38% with a fish consumption higher than twice a week. However, further studies are needed to confirm the mechanisms of action and the effects observed. In addition, maternal DHA intake contributes to the normal development of the eyes of the fetus and breastfed infants.Â
Contribute to normal fetal brain development
DHA is the major fatty acid in the brain. One study found significant effects on the performance of problem-solving tasks by 9-month-olds whose mothers had consumed DHA during pregnancy. Health authorities recognize that DHA consumption contributes to normal fetal brain development for a daily intake of 200 mg of DHA in addition to the recommended daily intake of omega-3 fatty acids for adults.
Contribute to the reduction of cardiovascular risks
Several large-scale studies have examined the impact of omega-3 intake on the secondary prevention of coronary heart disease, i.e., diseases affecting the arteries that feed the heart. For example, one study showed a 21% reduction in total mortality due to cardiovascular disease after omega-3 supplementation for populations that usually consume little fish. Omega-3s help lower triglyceride levels, prevent blood vessel inflammation and clot formation and reduce the growth of plaque that clogs blood vessels.Â
Summary
As this article explains, it is no wonder that omega-3s are becoming an increasingly important part of our lives. They are indeed important allies for the proper functioning of the body. It is therefore essential to include them more in our daily diet. Now you know what you must do when you go shopping! Â
Key take-home messages
- Alpha-linoleic acid (ALA) must be provided in the diet
- From ALA, the body can synthesize the other omega-3s
- Omega-3s are essential for eye health, fetal brain development, and heart health
- Flaxseed oil is the richest source of omega-3
- Smaller oily fish such as herring and sardines are also rich in omega-3 and less polluted than larger fish
References
Chong et al., Dietary ω-3 Fatty Acid and Fish Intake in the Primary Prevention of Age-Related Macular Degeneration, Archives of Ophthalmology, 2008
CIQUAL, Table de composition nutritionnelles des aliments, 2020
EFSA Panel on dietetic products, nutrition, and allergies, Scientific opinion on dietary reference values for alpha-linolenic acid, docosahexaenoic acid, and eicosapentaenoic acid, 2019
Jacobson, Beyond Lipids: The Role of Omega-3 Fatty Acids from Fish Oil in the Prevention of Coronary Heart Disease, Current Atherosclerosis Reports, 2007
Gray et al., Omega-3 fatty acids: a review of the effects on adiponectin and leptin and potential implications for obesity management, Nature, 2013
Judge et al., Maternal consumption of a docosahexaenoic acid-containing functional food during pregnancy: benefit for infant performance on problem-solving but not on recognition memory tasks at age 9 mo, The American journal of clinical nutrition, 2007
Parletta et al., People with schizophrenia and depression have a low omega-3 index, Prostaglandins, leukotrienes and essential fatty acids, 2016