Omega-3 Fatty Acids: Complete Guide to EPA, DHA and ALA

Omega-3: Vitamins? Not Quite.

The term "omega-3 vitamins" used in popular search queries is technically inaccurate — omega-3 fatty acids are not vitamins. Vitamins are organic compounds needed in small amounts and provide no energy. Omega-3s are essential fatty acids — they provide calories and serve as structural and functional components of cell membranes.

But the practical need is similar: the body cannot produce them in sufficient quantities, so we must obtain them from diet.

This guide explains the three main omega-3 fatty acids, why Western diets fall short, and how to make a smart choice.

TL;DR

• Omega-3 fatty acids are NOT vitamins — they are essential fatty acids
• Three main types: ALA (plant, short-chain), EPA and DHA (marine, long-chain)
• ALA conversion to EPA: ~5–10%; to DHA: <1% — meaning marine EPA/DHA is essential
• Modern Western diet: omega-6:omega-3 ratio is 15:1–20:1 (ideal would be ~4:1)
• WHO recommends 250–500 mg EPA+DHA per day for general health
• Forms: TG (closest to natural food), rTG (best bioavailability), EE (cheaper, lower bioavailability)
• Estonian context: Baltic herring, kilukonserv, cod liver oil — tradition and affordability

Three Omega-3 Fatty Acids: Comparison

ALA — Alpha-Linolenic Acid

Sources: flaxseed, chia, hemp, walnuts; rapeseed oil

ALA is the plant omega-3. The body uses it partially for energy and partially attempts to convert it to EPA and DHA. But conversion is extremely inefficient:

• ALA → EPA: ~5–10%
• ALA → DHA: <1%

This means that even if you eat flaxseeds daily, you do not get enough EPA or DHA. ALA is important — but it does not replace marine EPA/DHA.

EPA — Eicosapentaenoic Acid

Sources: fatty fish (herring, mackerel, salmon), cod liver oil, algal oil

EPA is the primary carrier of anti-inflammatory action in the omega-3 family. It generates resolvins and protectins — compounds that actively resolve inflammation, not merely suppress it.

EPA is also mood-linked: Martins (2009) meta-analysis showed EPA-dominant supplements are more effective in treating depressive symptoms.

DHA — Docosahexaenoic Acid

Sources: fatty fish, cod liver oil, algal oil (highest DHA content)

DHA is the structural component of the brain, eyes, and cell membranes. Approximately 60% of brain fatty acids are DHA. It is especially critical:

• For fetal brain development (third trimester)
• For newborn brain maturation
• For maintaining adult cognitive health

Why Modern Diets Fall Short

The agricultural revolution and food industry development have fundamentally altered human fatty acid intake.

Omega-6:Omega-3 Ratio: The Paradox

Stone-age humans: omega-6:omega-3 ratio ~1:1 to 4:1
Modern Western diet: ~15:1 to 20:1

Why? Omega-6 fatty acids (linoleic acid) are abundant in processed seed oils (sunflower, soybean, corn, rapeseed oil), which the food industry has used massively since the mid-20th century.

Omega-6 itself is not bad — it is also essential. But an excessively high omega-6:omega-3 ratio promotes inflammation, because omega-6 (arachidonic acid) generates more pro-inflammatory eicosanoids.

The Irony of Traditional Baltic-Russian Cuisine

In Baltic and Russian traditional cuisine, fatty fish (herring, sprats, salmon) appeared on the table far more often. Kilukonservid (canned sprats), salted herring, salmon soups — these were everyday staples, not delicacies.

This tradition automatically provided adequate EPA and DHA. The modern supermarket diet has disrupted this balance.

Fish Oil Forms: Which to Choose

Not all fish oils are created equal — the form significantly affects absorption:

Important: EE form is the basis of most budget fish oils. Improve absorption by taking it with a fatty meal. TG or rTG is a smarter choice if affordable.

Oxidation: Freshness Matters

Omega-3 fatty acids are susceptible to oxidation — particularly from heat, light, and oxygen exposure. Rancid fish oil:

• Tastes bad (so it goes untaken)
• Loses active compounds
• May produce harmful compounds

Always check:
1. Production date (use within 2 years)
2. Smell (should not be strongly fishy; mildly oceanic is normal)
3. Storage conditions (refrigerate after opening)
4. TOTOX value (some premium brands publish this)

Dosing

Safety: Above 3 g/day may prolong bleeding time. Consult a doctor if taking anticoagulants.

Fish Oil vs Algal Oil: Comparison

Algal oil is the original source — fish themselves get their DHA and EPA from algae. So algal oil sits higher in the food chain.

Frequently Asked Questions

Are omega-3s vitamins?

No. Vitamins are organic micronutrients; omega-3s are essential fatty acids — macronutrients. But both must come from diet, since the body cannot synthesize sufficient amounts.

Can a vegetarian get enough omega-3?

ALA is plentiful from flaxseeds, chia, etc. But EPA and DHA intake is problematic: conversion is inefficient. Algal oil is the only reliable EPA/DHA source for vegetarians and vegans.

When is the best time to take fish oil?

With a fatty meal — significantly improves absorption. Morning vs evening timing is not critically important.

Is fish oil suitable for children?

Yes — DHA is especially important for children's brain development. Use products specifically formulated for children (lower doses, tested for heavy metals).

Does fish oil help joint pain?

Several meta-analyses (Miller PE et al., 2014) have shown EPA and DHA reducing inflammatory joint pain. Effect appears after 8–12 weeks of regular use.

The Estonian Angle: Rediscovering Tradition

Estonia and the Baltic region have a long seafood tradition. Herring, cod, salmon, and kilukonservid (canned sprats) have been staples of Estonian cuisine for centuries — and automatically provided adequate EPA and DHA.

Affordable local options:

• Kilukonservid (canned sprats): ~1,000–1,500 mg EPA+DHA per 120 g can, cost ~1–1.50 EUR
• Salted herring: traditional, affordable, high EPA content
• Cod liver oil (kalamaksaõli): dual benefit of vitamin D + EPA/DHA in winter

Supplement cost: quality TG fish oil (90 capsules, 1,000 mg) costs 12–22 EUR in Estonia. Algal oil is higher (~25–40 EUR).

References

1. Calder PC. (2017). Omega-3 fatty acids and inflammatory processes: from molecules to man. Biochemical Society Transactions, 45(5), 1105-1115.
2. Simopoulos AP. (2002). The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomedicine & Pharmacotherapy, 56(8), 365-379.
3. Arterburn LM et al. (2006). Algae-oil capsules and cooked salmon: nutritionally equivalent sources of docosahexaenoic acid. Journal of the American Dietetic Association, 106(7), 1147-1154.
4. Neubronner J et al. (2011). Enhanced increase of omega-3 index in response to long-term n-3 fatty acid supplementation from triacylglycerides versus ethyl esters. European Journal of Clinical Nutrition, 65(2), 247-254.

Conclusion

Omega-3 fatty acids are among the most scientifically supported supplements — but only when you choose the right form and dose. Plant-based ALA sources do not replace marine EPA and DHA.

Simple approach: eat fatty fish 2–3 times per week (herring, mackerel, salmon) and supplement with quality TG or rTG fish oil on days when that is not possible. For vegans, algal oil is the best alternative.

See also:

• EPA (Eicosapentaenoic Acid): Benefits, Dosing and Best Sources
• Omega-3 + D3 + K2: The Science Behind the Triple Stack
• Vitamin D3 in Estonia: Why It Matters and How to Choose the Right Dose

See also:

• Vitamin D3 Overdose: Symptoms, Safe Limits, and What to Do
• Vitamin B3 Deficiency: Symptoms, Causes, and How to Fix It
• Vitamin D 25(OH)D Blood Test: What It Measures and How to Interpret Results