Krill Oil Vs Fish Oil Vs Algae Oil: Is There A Difference?

How to make an informed choice about omega-3 supplements

If you’re interested in good nutrition, you probably have heard about fish oil and krill oil. Krill are the tiny crustaceans being harvested in the Antarctic for fish food and for their oil, which is used in supplements for humans. Fish oil is harvested from a variety of species, especially menhaden, a very oily fish that has limited market value as a food fish.

There are lots of people on the internet trying to convince you to buy their brand of both of these rich sources of omega-3s (EPA and DHA), fats that our bodies and brains need to function fully. Then there are those vegetarian sources such as hemp and chia. All of these are good, and there are unique benefits to each.

First let’s take a look at krill oil. Beyond omega-3s, krill oil also contains phospholipids and astaxanthin, a powerful antioxidant. Antioxidants enter your blood and scavenge for DNA-damaging free radicals. Free radicals are formed when a molecule in your cells loses an electron. This can be triggered by the presence of environmental factors, such as pollution, radiation, herbicides or smoking (among many other agents). Free-radical activity can even be triggered by consumption of excessive calories, such as those found in simple sugars.

Free radicals are unstable and they try to steal their needed electron from another compound – a method used to gain stability. The compound from which the electron is stolen sometimes becomes another free radical, which can begin a chain reaction that will damage living cells, something that accumulates with age.

The phospholipids found in krill oil are the stuff of which our cell walls are made. Phospholipids are also rapidly absorbed into our bodies. Fatty acids bound to the phospholipids are fed into a complex signaling cascade known as the eicosanoid system, which regulates a huge array of the body’s functions.

How does krill oil compare to fish and algae oil?

Is it any better for you than fish oil or an algae-based (vegetarian) omega-3? It depends on what you want.

If you’re a vegetarian, omega-3s from algae oil, hemp oil and chia are obviously the way to go. However, research is pretty clear that the human body more fully converts the marine oils to EPA and DHA.

First, let’s explain some of the terms we’ll be using. Phospholipids are made up of two fatty acids, which are bound through a phosphate link to the essential nutrient choline. Choline is very important for your brain. The fatty acids from cold-water marine creatures like krill are often omega-3 fatty acids. Therefore, the phosphatidylcholine from krill has a unique benefit to structures like the brain, and can enhance attributes like mental sharpness.

Many of the fats we ingest from food, vegetable oils, and fish are in the form of triglycerides. Tri means “three,” and triglycerides have three fatty acids bound to a simple backbone. Triglycerides are a source of energy for our bodies, containing twice much energy as carbohydrates or proteins. However, triglycerides cannot pass through cell membranes freely. Special enzymes on the walls of blood vessels called lipoprotein lipases must break down triglycerides into free fatty acids and glycerol. High levels of triglycerides in the body are linked to atherosclerosis (vascular disease), heart disease, and stroke.

The following should shed some light on the differences between the main supplemental sources of omega-3s – fish oil, algae oil and krill oil.


Fish oil – contains EPA, DHA and triglycerides

Algae oil – contains EPA, DHA and triglycerides

Krill oil – contains EPA, DHA, choline, phospholipids, astaxanthin, no triglycerides

You are likely to read that a typical fish-oil capsule contains more DHA and EPA than a capsule of krill oil. This is true, but you are less likely to hear that the EPA and DHA in krill oil are bonded to phospholipids, which have unique attributes in human biology. There are several studies now underway that examine the potential bioavailability benefits of phospholipid-based omega-3 fatty acids.

Krill oil, being new to the market and more difficult to harvest and refine into supplements, are presently more expensive than fish and algae oils. However, this scenario is likely to change as the species of fish used to produce oil for human consumption are becoming rarer as the demand for fish oil rises. And as the krill harvests become larger, the price of krill oil will fall, bringing it more into line with fish oil.

As yet, the body of scientific research on krill oil is presently much smaller than the research on sources of omega-3 fatty acids from fish oil. But you can read the summaries of several such krill-oil studies here, here and here.