Let’s Compare Krill Oil and Fish Oil

Is there really any difference?

You may have heard about krill oil by now. Krill are the tiny crustaceans being harvested in the Antarctic for fish food and for their oil, which is used in supplements for humans. People are beginning to wonder if oil is better for you than fish oil.

Krill oil is another rich source of omega-3s, beyond fish oil and vegetarian sources such as hemp and chia. 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. The phospholipids found in krill oil 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 bewildering array of the body’s functions.

So is krill oil any better than fish oil?

… or is krill oil any better for you than an algae-based (vegetarian) omega-3? It depends on what you want.

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 really 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.

While there is some excellent information about sources of omega-3 fatty acids on the web, there is a great deal of writing that is focused on selling a specific brand of product. This makes it tough for us regular folks who are looking for all the promised benefits of taking omega-3 supplements to figure out what to spend our money on.

Perhaps the following chart will shed some light on the subject. Without endorsing any particular form of omega-3 supplements, let’s illustrate some simple comparisons between several of the forms in which omega-3s come – fish oil, algae oil and krill oil.

OMEGA-3S SOURCE COMPARISON
	Fish oil	Algae oil	Krill oil
CONTENTS
EPA	x	x	x
DHA	x	x	x
Choline			x
Phospholipids			x
Astaxanthin			x
Triglycerides	x	x

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.

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.

James Townsend is editor in chief of WellWise.org, a nonprofit organization for the dissemination of science-based information about supplements, nutrients and strategies for health.