4Optional

Cod liver oil

Also sold as Fish liver oil

Omega-3 plus substantial vitamin A and D — the vitamin A is why it isn't simply interchangeable with fish oil.

TrustedSupp Tier System™ · Tier 4Take by choice, or not at all

Check before you startThis one has documented interactions with medication classes where the consequences are serious. If you take any prescription medicine, run it past a pharmacist before starting.

Evidence strength

60/100Moderate

WEAKLIMITEDMODERATESTRONGVERY STRONG

What the evidence supports: supplying omega-3, vitamin A and vitamin D; outcome benefits track those nutrients individually.

This scores how well-supported the claim above is — not how much benefit you personally would get. A high score on a narrow claim does not extend to everything the product is marketed for.

How long to take it

Ongoing is possible, but only if total vitamin A and D from all sources stays within limits.

Who it's actually for

People who want vitamin D and omega-3 in one product and don't take other retinol sources.

Safe upper limit

Unverified

Governed by preformed vitamin A (3,000 mcg RAE/day for adults) and vitamin D (100 mcg / 4,000 IU/day)

Retinol from cod liver oil accumulates. Taking extra 'for more omega-3' can push vitamin A past the upper limit, especially alongside a multivitamin or liver supplements.

No source or citation attached yet.

Interactions to know about

Blood thinners / antiplatelets — Warfarin, apixaban, rivaroxaban, clopidogrel, aspirin
Retinoids — Isotretinoin, acitretin

Other supplements:

Run your full list through the interaction check.

Practical notes

Avoid or limit in pregnancy unless your clinician agrees, because of the preformed vitamin A.
If you want more omega-3, add plain fish oil rather than more cod liver oil.
Check the label for vitamin A per serving — it varies a lot between brands.