What Is Omega-3 and Why Is It Important?

Omega-3 fatty acids are polyunsaturated fatty acids that cannot be synthesized by the human body and therefore must be obtained through diet. They are classified as “essential fatty acids” for this reason. They play a role in numerous biological processes, from maintaining cell membrane integrity to regulating inflammation.

There are three main types of omega-3 fatty acids:

• ALA (Alpha-linolenic acid)

• EPA (Eicosapentaenoic acid)

• DHA (Docosahexaenoic acid)

ALA is plant-based. EPA and DHA are primarily found in marine sources and are considered the more biologically active forms in terms of direct health effects. The human body can convert ALA into EPA and DHA, but the conversion rate is low (generally less than 5–10%) (NIH Office of Dietary Supplements, 2023).

What Does Omega-3 Do in the Body?

Cellular structure and membrane function

Omega-3 fatty acids are structural components of cell membrane phospholipids. They influence membrane fluidity and cellular signaling. DHA, in particular, is highly concentrated in brain and retinal cell membranes (NIH, 2023).

Cardiovascular health

The effects of omega-3 fatty acids on the cardiovascular system are among the most extensively studied areas.

Scientifically established effects include:

• Reduction of triglyceride levels (particularly EPA and DHA at higher doses)

• Modest reductions in blood pressure

• In some studies, association with reduced risk of cardiovascular events

The American Heart Association (AHA) recommends consuming at least two servings of fatty fish per week. In individuals with elevated triglycerides, prescription omega-3 formulations may be used under medical supervision (AHA Scientific Advisory, 2019).

Brain development and neurological function

DHA is a major structural component of brain tissue. It plays a critical role in fetal and early childhood brain development. For this reason, adequate DHA intake during pregnancy and breastfeeding is important (EFSA, 2010).

Research on cognitive performance in adults is ongoing. While findings are not entirely consistent regarding protective effects, the structural importance of DHA in neurological function is well established.

Eye health

DHA is highly concentrated in retinal tissue. Inadequate DHA intake has been associated with impaired visual development and function. As a result, DHA supplementation in infant formulas has become standard practice in many countries (EFSA, 2010).

Regulation of inflammation

Omega-3 fatty acids are involved in the synthesis of inflammatory mediators and may help modulate certain pro-inflammatory processes. For this reason, they have been studied as supportive therapy in inflammatory conditions such as rheumatoid arthritis. However, they are not a substitute for medical treatment (NIH, 2023).

What Is the Recommended Daily Intake of Omega-3?

Official recommendations include:

• World Health Organization (WHO): An average daily intake of 250–500 mg of EPA + DHA for adults

• EFSA: 250 mg of EPA + DHA per day is considered adequate for the general adult population

• Adequate intake for ALA is approximately 1.1 g/day for women and 1.6 g/day for men (NIH, 2023)

High-dose omega-3 supplementation (particularly above 3 grams per day) should only be used under medical supervision.

What Are the Dietary Sources of Omega-3?

Marine sources

• Salmon

• Mackerel

• Sardines

• Anchovies

• Herring

These fish are rich in EPA and DHA.

Plant sources

• Flaxseed

• Chia seeds

• Walnuts

• Canola oil

• Soybean oil

These sources provide ALA. However, the conversion of ALA to EPA and DHA in the body is limited.

Alternative source: Algal oil

Algal oil contains DHA (and in some products EPA) and is an important plant-based alternative, especially for individuals following vegan or vegetarian diets.

Why Are Omega-3 Supplements Used?

Supplements are typically preferred in the following situations:

• Individuals who do not consume sufficient fish

• Patients with elevated triglyceride levels (under medical supervision)

• During pregnancy and breastfeeding to support DHA intake

• To prevent DHA deficiency in plant-based diets

Omega-3 supplements do not replace medical treatment. Individuals taking anticoagulant medications or preparing for surgery should consult a healthcare professional before use.

Omega-3 Production and Encapsulation Process

Omega-3 supplements are typically derived from fish oil or algal oil. The production process involves several quality and safety steps.

Extraction of crude oil

Crude fish oil is obtained from oily fish (often small pelagic species) using pressing or centrifugation methods.

Purification and refinement

The crude oil is purified to remove heavy metals, dioxins, and other environmental contaminants. Techniques such as molecular distillation may be used to enhance purity and standardize EPA/DHA concentrations.

International quality standards (such as the GOED monograph) define oxidation limits and purity criteria.

Concentration and chemical forms

Omega-3 fatty acids are available in different chemical forms:

• Triglyceride form

• Ethyl ester form

• Re-esterified triglyceride form

• Phospholipid form (e.g., krill oil)

Bioavailability may vary among forms, although clinically meaningful effects are primarily related to total EPA + DHA dosage.

Protection against oxidation

Omega-3 fatty acids are sensitive to oxidation. During production, the following measures may be applied:

• Low-temperature processing

• Nitrogen atmosphere

• Addition of antioxidants (such as tocopherols)

Encapsulation (softgel production)

The purified oil is typically filled into gelatin-based soft capsules. Vegan products may use plant-based capsule materials.

Some manufacturers apply microencapsulation technology to convert omega-3 into powder form. This approach:

• Reduces oxidation

• Masks taste and odor

• Facilitates incorporation into functional foods

Microencapsulation methods include spray drying and complex coacervation techniques (Food Research International, 2021).

What Should Be Considered When Using Omega-3?

• The total EPA + DHA content should be clearly stated on the label.

• Oxidation values and quality certifications are important.

• High-dose use should be supervised by a physician.

• Individuals using blood thinners should consult a healthcare provider.

• Products should be stored in a cool, dark environment.

Omega-3 fatty acids, particularly EPA and DHA, are essential nutrients involved in multiple physiological processes ranging from cardiovascular health to brain development. Because the body cannot produce them, they must be obtained regularly through diet. Fatty fish consumption is the most natural source; supplements may be used when necessary and under appropriate conditions.

Scientific evidence strongly supports the triglyceride-lowering effects of omega-3 fatty acids. In other health areas, outcomes may vary depending on individual factors and dosage.