Quick answer
Fish oil supplements provide the omega-3 fats EPA and DHA. Health New Zealand lists fish oil among popular supplements, and some people use it for high blood triglycerides — a situation for a GP to manage. Check EPA and DHA milligrams per serve, and whether it's triglyceride or ethyl ester form; algae oil suits vegans.
- 01
Two serves of oily fish per week is the general food-first approach; there is no official New Zealand supplement intake target for the general population.
- 02
Compare EPA and DHA milligrams per serve, not the total "fish oil" weight shown on the front of the label.
- 03
Health New Zealand lists fish oil among the popular supplements people take, and specifically mentions high blood triglycerides as a reason some people use it — talk to a GP first rather than self-diagnosing.
- 04
Triglyceride-form omega-3 is generally better absorbed than ethyl ester form; algae oil is a vegan source of DHA in triglyceride form.
What does a fish oil supplement actually provide?
Fish oil supplements are a concentrated source of two long-chain omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These are different from the shorter-chain omega-3 (ALA) found in plant foods such as flaxseed and walnuts, which the body converts to EPA and DHA only in small amounts.
Healthify (the New Zealand consumer health information service) notes there are no official New Zealand recommendations for fish oil supplement dosing, and that it is best to get omega-3 from food where possible — a diet that includes around two serves of oily fish per week is generally considered adequate for most healthy adults.
How should you read a fish oil label?
Look at the EPA and DHA amounts listed per capsule or serve, not the total fish oil content. A label might state "Fish oil 1.5g equiv." but only 450mg of that is actual EPA plus DHA — the rest is other fatty acids and material that is not omega-3.
The omega-3 in a supplement is chemically present either as a triglyceride (the natural form found in fish) or as an ethyl ester, a more processed form created to concentrate omega-3 during manufacturing. Research reviewing New Zealand fish oil products found ethyl esters are common because they are cheaper to produce, but they are typically less well absorbed than the triglyceride form. If the form matters to you, look for wording such as "triglyceride," "TG" or "re-esterified triglyceride (rTG)" on the label — many concentrated products default to ethyl ester without stating it prominently.
When might a fish oil supplement be relevant?
Health New Zealand includes fish oil among the popular supplements bought in New Zealand and specifically notes that some people take omega-3 fish oil supplements if they have high triglycerides in their blood — a fat measured on a standard blood test. This is a clinical situation that should be assessed and monitored by a GP, not something to self-diagnose from symptoms.
Outside of that specific context, most healthy people without a diagnosed need can meet their omega-3 requirements through oily fish and do not require a supplement. If you take blood-thinning medication, are pregnant, or have a bleeding disorder, speak with a health professional before starting a fish oil supplement.
What about vegans and vegetarians?
EPA and DHA are found almost exclusively in seafood and fish oil, so people who avoid fish need an alternative source if they want these specific long-chain omega-3s rather than relying on the plant-based ALA conversion pathway alone.
Algae oil is produced from the same microalgae that fish ultimately obtain their omega-3 from, and is naturally in triglyceride form. It typically provides DHA, and some algae-oil products also provide EPA — check the label for the actual EPA and DHA amounts per serve, exactly as you would for a fish oil product.
People also ask
Frequently asked questions
Is fish oil approved by Medsafe as effective?
No. Fish oil is sold in New Zealand as a dietary supplement, not a medicine, so it is not assessed by Medsafe for safety or effectiveness before sale. Manufacturers are responsible for ensuring their claims and product quality are appropriate.
Can a fish oil supplement replace eating fish?
Not entirely. Oily fish provides protein, vitamin D and other nutrients alongside omega-3, so a supplement is a partial substitute at best. Food-first guidance in New Zealand suggests aiming for around two serves of oily fish per week where practical.
Is algae oil as good as fish oil?
Algae oil is a legitimate source of DHA (and sometimes EPA) in triglyceride form, making it a suitable vegan or vegetarian alternative. Compare the EPA and DHA content per serve between products rather than assuming one source is automatically superior.
Evidence and further reading
This guide provides general education, not diagnosis or individual medical advice. Follow product labels and speak with an appropriately qualified health professional when you are pregnant, nursing, taking medication or managing a health condition.
Keep learning
