Omega 3: Comprehensive Guide to Its Benefits and Uses

Published: 30 April, 2025 | 10'

Surely you have heard that omega 3 is good for the heart, but these healthy fats also play roles in many other processes in our body. So much so that omegas fall under the category of essential fatty acids, due to their importance in our health.

In addition to their importance in the cardiovascular system, we will explain the role they play in other functions of our body and how to incorporate them into your daily diet.

What are Omega 3 and why are they so important?

Omega 3 fatty acids are a type of polyunsaturated fat, which are fats that have a beneficial effect on our body, along with omega-6. This type of fat is necessary for cell growth, brain function, and the cardiovascular system, where they have a positive effect on various processes such as the reduction of LDL cholesterol, or so-called “bad” cholesterol.

Depending on the source of extraction, omega 3s can be of plant or animal origin. The most commonly known are “fish oils,” as certain fish are the main source of these fatty acids, and this is the usual way to find them in dietary supplements.

Types of omega 3 fatty acids: EPA, DHA, and ALA

The three main omega 3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).

EPA supports wellbeing and functions in the cardiovascular system, for instance, by helping to regulate triglyceride levels, and it is also involved in the nervous system. DHA is an essential nutrient for brain development and its proper functioning, especially during the growth of the baby in pregnancy and childhood, as well as for the health of our eyes and brain, also participating in cognitive function. ALA is a precursor to the other two, has antioxidant capabilities, and also supports the cardiovascular system.

Proven benefits of omega 3 for your health

The benefits of omega 3 affect almost all levels, although mainly on the cardiovascular system and our brain, and it has been shown that they regulate pro-inflammatory factors and positively influence ocular health.

Omega 3 and the heart

Our cardiovascular system is composed of the heart and blood vessels, meaning the entire network of veins and arteries that distribute oxygen and nutrients throughout our body. The benefits of omega 3 fatty acids on our cardiovascular system are mainly attributed to EPA and DHA. Specifically, according to EFSA, EPA and DHA contribute to the normal function of the heart.

The use of omega 3 has been extensively reviewed clinically and has been shown to significantly reduce triglyceride levels, a type of fat that accumulates in the blood and increases the likelihood of cardiovascular risk, as well as regulating the elasticity of blood vessels, which helps maintain blood pressure within normal values.

They also result beneficial for the blood clotting process, which favours cardiovascular wellbeing and reduces the risk of heart attacks, as well as potentially contributing to stabilising the electrical activity of the heart, thereby reducing the likelihood of irregular heartbeats or arrhythmias.

Regulation of anti-inflammatory activity by omega 3

The fatty acids participate in modulating pro-inflammatory factors through various mechanisms, as omegas 3 and 6 are involved in their formation. This property attributed to omega 3 particularly impacts the cardiovascular system, as maintaining a low level of inflammation is associated with better cardiac function, and it also positively affects brain health.

Omega 3 and mental health: mood stability and cognitive function

Omega 3 fatty acids, particularly in greater measure DHA, are essential for brain development and function, especially during fetal development in pregnancy and childhood, as they are a structural component of the brain, specifically in neurons. Moreover, particularly in older ages, DHA contributes to maintaining brain health and cognitive function. In fact, a study published in Nutrition Hospitalaria highlights its positive effect on brain function in older adults, particularly on memory, speed of information processing, and verbal fluency. Another meta-analysis published in Frontiers in Aging Neuroscience showed that adequate DHA intake is associated with a lower risk of cognitive decline.

In addition to its role in learning and memory processes, omega 3 is involved in mood and helps maintain mental health. EPA has demonstrated its benefit in mood disorders, which are related to inflammation levels. It also regulates the levels of the neurotransmitters dopamine and serotonin, which are associated with emotional wellbeing.

Omega 3 and eye health

DHA is a key component of cell membranes in the retina, where it plays a role in structural and functional integrity. In fact, this fatty acid is crucial during pregnancy and infancy for the proper development of visual function.

Is it related to dry eye?

Dry eye can be due to various factors such as the environment, certain conditions like allergies or colds, exposure to pollutants, or even intrinsic causes like natural ageing.

There are multiple trials that have studied the role of omega 3 in this area with varied results. Some of them show improvements in symptoms by regulating pro-inflammatory factors in the tear glands and, as a consequence, improving tear production, although more research is needed in this area to obtain conclusive results.

Macular degeneration

Vision deterioration is common with age and can sometimes lead to blurred vision, difficulty distinguishing details, and other symptoms collectively known as macular degeneration, a very common disorder in adults over 60 years old. The role of omega 3 in reducing the chances of developing this condition has been studied, with contradictory results regarding its direct benefit, thus more clinical research is needed.

Omega 3 in pregnancy and breastfeeding: A gift for your baby and yourself

The gestation period is one of profound changes in a woman's body, a phase of continuous growth and development of cellular tissue for both the fetus and the mother, in which omega 3 and omega-6 play an essential role, thus the requirements for these fatty acids increase during this time.

In general, omega 3 intake during pregnancy has been associated with numerous benefits for both the fetus and the mother.

Benefits for fetal development: brain, vision, immune system

The third trimester of pregnancy is characterised by the baby's growth, not just physically and in terms of weight but also of important organs like the brain and lungs, and the baby can now see and hear and will prepare for birth.

Omega 3 DHA plays an important role especially during this stage, as it helps with the neurological development and nervous system of the fetus. Its activity is also related to the development of nerve impulses and neuronal growth, which contributes to learning and memory processes.

Many studies confirm the role of omega 3 in motor development, vision, and cognitive improvement, but it is also associated with a lower risk of premature births and low birth weight.

Importance for mother's health

Omega 3 intake during pregnancy not only benefits fetal development but also the mother, specifically regarding her cardiovascular system and mood. For this reason, it is essential that the mother ensures an adequate intake of fatty acids to meet her own needs and those of the baby, and it is very common for dietary supplements recommended during pregnancy to contain omega 3 in their formulations.

Sources of omega 3 and how to incorporate it into your diet

Our body does not produce omega 3 fatty acids on its own, so we need to obtain them through our diet every day or in the form of dietary supplements.

There are two well-differentiated sources of omega 3 in our diet:

• Those derived from plant sources contain ALA, which is the short-chain omega 3 form. The ALA is converted in our body into long-chain fatty acids, such as DHA and EPA.
• While animal sources, specifically marine origin, contain EPA and DHA which are indeed long-chain. Their function complements that of the short-chain, so both forms are necessary in our body.

Foods rich in omega 3

• Fish is the main source of omega 3 EPA and DHA, found in fatty fish such as salmon, sardines, mackerel and fish oil. 
• On the other hand, omega 3 ALA is found in plant sources such as&#xA0>walnuts and chia or flax seeds, soybean oil and other plant-based sources. 
• You can also find omega 3 in fortified foods such as cereals, infant formulas, margarines, yoghurts and even milk.

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Omega 3 supplements: when to take them, dosage and precautions

In addition to finding sources of omega 3 in foods, there are dietary supplements that contain the EPA and/or DHA forms, as well as plant-based oils providing ALA, among others. The sources of EPA and DHA in dietary supplements are obtained from marine sources such as fish oil, krill oil or cod liver oil.

The ideal is to take omega 3 dietary supplements alongside one of the main meals, such as lunch or dinner, and preferably at the same time every day, following the dosage indicated by the manufacturer.

There is no general recommended daily intake of omega 3, and this also depends on age and sex, or whether there is any personal condition, although theWorld Health Organization (WHO) advises a daily intake of between 250 and 2,000 mg, which equates to consuming fish and seafood around 3 or 4 times a week.

For its part, theEuropean Food Safety Authority (EFSA) has monitored supplementary intake of combined EPA and DHA in doses of up to 5 g per day, without any issues regarding its safety for adults. Dietary recommendations for EPA and DHA based on cardiovascular risk considerations for European adults range from250 to 500 mg per day.

Before starting any dietary supplement, it is advisable to consult a healthcare professional to determine the most suitable option depending on our personal requirements.

The science behind omega 3: Recent studies and advances 

Currently, the role of omega 3 in our bodies and its effects on various processes such as cardiovascular health, cellular ageing and brain health. is still under study.

Current research on the benefits of omega 3

A recent study published in Nature Aging revealed the positive effects of omega 3 combined with vitamin D and regular exercise on the delay of biological ageing  in adults over 70 years old.

Regarding brain health, a study published in Nutrients by researchers from the Hospital del Mar Research Institute suggests that high levels of omega 3 may be associated with a lower risk of dementia, being beneficial for cognition.

Of course, these studies require further research to reach conclusive results in these areas.

Myths and truths about omega 3

Today, the consumption of dietary supplements for general care and well-being is becoming increasingly common, but while there is more evidence regarding them, information is continuously published online about benefits that may not be substantiated by official sources or backed by scientific studies  and lead to confusion among consumers. 

 Does omega 3 really help with weight loss?

As mentioned earlier, omega 3 fatty acids are allies in maintaining low inflammatory levels and could be involved in the processes of fat metabolism due to their effect on body lipids.

For these reasons, their role on body weight has been studied in the form of supplements with positive results in non-representative groups, so more research is needed in this field to achieve conclusive results regarding their action in weight loss.

Is it safe to take omega 3 supplements long-term?

It is recommended to take any omega 3 supplement for at least three months to evaluate its results in conjunction with a healthcare professional, and to continue the intake if deemed necessary.

What type of omega 3 is best?

Our body requires all types of omega 3 for its proper functioning, although in the form of dietary supplements, the DHA and EPA forms are more commonly found.

Conclusion: Omega 3, a fundamental pillar for a healthy life

Omega 3 fatty acids are essential due to their presence in a large number of processes in our body, primarily in the cardiovascular system, but also in the formation of new cells and brain health.

Summary of the benefits of omega 3 for health

As we have seen, the action of omega 3 is important at the cardiovascular level, as it helps to maintain normal cholesterol and triglyceride levels as well as blood pressure, but it also has an action on cognitive function in our brain. Additionally, they are particularly important during pregnancy and childhood for development and growth, both physically in the formation of essential organs and in brain function.

The importance of including omega 3 in your daily diet

Since our body does not naturally produce omega 3, we must ingest them through our diet daily either through foods, primarily found in fish and nuts, or through dietary supplements.

If you want to know more about your cardiovascular system…

• Omega 3, essential for development
• The health importance of Omega 3, 6, 7 and 9
• The role of Omega 3 and your heart
•  

Content reviewed by specialists from the Scientific Information area of MARNYS. This article is informative and does not replace a consultation with a specialist.