Omega-3 (EPA & DHA)
Omega-3 fatty acids - particularly EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) - are essential fats that play a crucial role in many aspects of health. They are structural components of brain and nerve tissue, influence inflammation pathways, and support heart and immune health.
Because our bodies cannot produce EPA or DHA in meaningful amounts, we rely on dietary intake. For those who don’t eat fish regularly, or who have higher demands due to lifestyle or health context, omega-3 supplements can provide additional support alongside a balanced diet.
What are omega-3 fats?
Omega-3 refers to a family of essential fatty acids that the body cannot make on its own. The two most studied forms are:
EPA (eicosapentaenoic acid) - known for its role in inflammation balance and mood support
DHA (docosahexaenoic acid) - essential for brain, nerve and eye function
These are found primarily in oily fish.
Plant sources contain ALA (alpha-linolenic acid), which the body must convert into EPA and DHA. But this process is inefficient, which is why direct sources (fatty fish) and supplements are of interest.
Omega-3 supplements usually contain a blend of EPA and DHA, or higher-EPA formulas depending on the intended purpose.
Why omega 3 supplements are used
Omega-3 supplements are commonly used to support:
general inflammation balance
brain health and cognitive function
mood and emotional wellbeing
heart and cardiovascular health
skin health and moisture balance
joint comfort
eye health
overall wellbeing when dietary fish intake is low
People who avoid fish, follow plant-based diets or eat very small amounts of seafood often benefit most from supplementation.
What does the research say?
Research consistently shows that EPA and DHA play key roles in brain and nervous system function, healthy inflammatory regulation, cardiovascular health - in particular they help maintain normal blood triglyceride levels, mood and anxiety and eye and skin health.
Evidence also suggests that:
most UK adults do not meet recommended omega-3 intake
EPA may be more influential for mood pathways
DHA is crucial during pregnancy and early development
people who regularly eat oily fish often have better omega-3 status
When should it be considered?
Omega-3 supplementation may be more evidence-based in people with diagnosed cardiovascular disease or mild cognitive impairment than in generally healthy people. In these contexts, doses and forms studied in trials are typically 2–3 grams per day of combined EPA and DHA.
But omega-3 may also be useful if you:
eat little or no oily fish
follow a vegetarian or vegan diet (algal oil is a good alternative)
experience dry skin or dry eyes
have a highly stressed lifestyle
have low mood or emotional fluctuations
have joint stiffness or discomfort
want to support cardiovascular health
are pregnant or breastfeeding (with appropriate product choice)
It can also be considered alongside dietary and lifestyle support when inflammation pathways appear active.
When to exercise caution
High doses of omega-3 can increase bleeding risk and may interact with anticoagulant medications. People on blood thinners, those with bleeding disorders, or with upcoming surgery should discuss omega-3 supplementation with a healthcare provider.
Quality and oxidation status of supplements varies; rancid fish oil is not beneficial and purified, sustainably sourced oils are preferable. GI discomfort or reflux or 'fishy burps' can sometimes occur with lower-quality products.
What else to consider?
The observational associations between fish intake and health outcomes likely reflect the overall dietary pattern (which includes fish), not fish or omega-3 alone. People who eat fish also tend to eat more vegetables, have better overall nutrition and different lifestyle patterns.
Omega-3 can be an excellent support, but it shouldn’t replace basic dietary and lifestyle approaches for mood, inflammation or cardiovascular health.
Before focusing on supplementation, it’s important to consider:
overall diet quality (especially including fibre and colourful plant foods)
stress and recovery patterns
movement and cardiovascular activity
sleep consistency
the types of fats eaten day-to-day
A balanced lifestyle helps the body utilise omega-3s far more effectively.
Food sources of omega-3
For those eating fish, fatty fish such as salmon, mackerel, sardines and herring provide abundant EPA and DHA. For those not eating fish, algae-based supplements are an option, and plant sources (walnuts, flaxseeds, chia seeds) provide ALA, though conversion to EPA and DHA is limited. More broadly, a dietary pattern including varied fats (olive oil, nuts, seeds, avocado, fish), regular movement, adequate sleep and stress management has more substantial evidence than omega-3 supplementation alone.
Supplements can complement these foundations when intake is low or needs are higher.
Book a free call
Supplements are a minefield. If you’re unsure whether omega-3 supplementation might support your goals, or whether dietary changes would be enough, we can explore this together. Book your free call with me.
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