Fish Oil vs Omega-3 vs Krill Oil: What’s the Difference?

"Omega-3," "fish oil" and "krill oil" get used as if they mean the same thing — but they don't. Omega-3 is the nutrient. Fish oil and krill oil are just two ways to get it (and algae oil is a third). Here's how they actually compare, and which omega-3 supplement makes the most sense in Malaysia.

First, what omega-3 actually is

Omega-3 is a family of fats. Three of them matter:

• EPA and DHA — the marine omega-3s, found in oily fish and other sea sources. These are the ones with the most research behind them and the ones your body uses directly.
• ALA — the plant omega-3, found in flax, chia and walnuts. Your body converts only a small fraction of it into EPA and DHA, so it's not an efficient substitute.

So an "omega-3 supplement" is really a category. What separates the products on the shelf is the source — and how much EPA and DHA each one actually delivers.

Fish oil

Oil pressed from oily fish like sardines, anchovies and mackerel. It's the most common source for a reason.

• Strengths: the highest concentrations available, the best value per milligram of omega-3, and the easiest way to hit a real dose — a concentrated oil can give 900mg of omega-3 in a single capsule.
• Watch for: a fishy aftertaste if the oil is low quality or oxidised, and the halal status of the capsule shell (check the gelatin).

Krill oil

Oil from Antarctic krill — tiny shrimp-like crustaceans. It carries EPA and DHA in a phospholipid form and naturally contains astaxanthin, which gives it a red colour.

• Strengths: smaller softgels and often less fishy "repeat."
• Watch for: much less omega-3 per capsule (often just 60–120mg), so it takes more capsules to reach a meaningful dose; a notably higher price per milligram of omega-3; a shellfish-allergy caution; and halal options are harder to find.

Algae oil (the plant-based option)

Omega-3 grown from marine algae — the original source the fish get it from in the first place. If you want a "natural," plant-based omega-3, this is it.

• Strengths: suitable for vegetarians and vegans, no fishy taste, and it sidesteps the pork and shellfish questions entirely.
• Watch for: it's usually DHA-heavy with less EPA, and it tends to cost more per milligram.

Side by side

Whatever the source, compare the same way: add up the EPA + DHA per capsule, then work out the cost per day to reach your target. The headline "mg" on the front doesn't tell you either.

So which should you choose in Malaysia?

• For most people: concentrated fish oil. It's the best value and the easiest way to get a real omega-3 dose. Just check it's halal-certified and MAL-registered.
• Krill oil is fine if you prefer small capsules and don't mind paying more — but check the actual omega-3 number, not just the price.
• Algae oil is the clear pick if you're vegetarian, vegan, or simply avoid fish.

For the full checklist on reading a label — EPA, DHA, MAL, halal and cost per day — see how to choose a fish oil supplement in Malaysia.