Most people who take an omega-3 supplement are familiar with fish oil or krill oil. Far fewer have heard of wax ester-based omega-3 oils.
Yet wax esters are a naturally occurring form of marine fat found throughout the ocean food web. One particularly rich source is the tiny North Atlantic marine copepod Calanus finmarchicus.
Oil derived from Calanus finmarchicus is unusual because most of its fatty acids are naturally bound in the form of wax esters, rather than primarily as the triglycerides commonly found in fish oil or the phospholipids associated with krill oil.
That difference in molecular structure is what makes Calanus oil—and wax ester-based omega-3 oils—a distinct category of marine oil.
Omega-3 Is a Fatty Acid, Not a Type of Oil
The term “omega-3” describes a family of polyunsaturated fatty acids.
Some of the best-known marine omega-3 fatty acids include:
- EPA — eicosapentaenoic acid
- DHA — docosahexaenoic acid
- SDA — stearidonic acid
But EPA and DHA do not normally exist by themselves inside an oil. They are attached to other molecules.
The molecular form carrying the fatty acid can differ substantially depending on the source of the oil.
Traditional fish oil commonly contains fatty acids bound to triglycerides. Concentrated omega-3 products may also contain re-esterified triglycerides or ethyl esters.
Krill oil contains a substantial portion of its omega-3 fatty acids in phospholipids.
Calanus oil is different.
Research examining oil derived from Calanus finmarchicus has found that approximately 80–90% of its fatty acids are associated with wax esters.1, 2
Understanding that distinction requires understanding what a wax ester actually is.
What Is a Wax Ester?
A wax ester is a naturally occurring lipid formed when a fatty acid is chemically linked to a long-chain fatty alcohol.
That structure is fundamentally different from a triglyceride.
A triglyceride consists of three fatty acids attached to a glycerol backbone:
A wax ester instead consists of a fatty acid attached to a long-chain fatty alcohol:
This may sound like a small chemical distinction, but it gives wax esters different physical and digestive characteristics from conventional triglyceride oils.
Wax esters are extremely hydrophobic—meaning they strongly repel water—and are used throughout nature for energy storage, protection and buoyancy.
In Calanus finmarchicus, they serve another particularly important purpose: long-term energy storage.
Why Does Calanus finmarchicus Produce Wax Esters?
Calanus finmarchicus is a small copepod, typically only a few millimeters long, that lives throughout the cold waters of the North Atlantic.
Although tiny, it occupies an enormously important position in the marine food web.
Calanus feeds primarily on phytoplankton and is then consumed by fish and other marine animals. In this way, it acts as an important link between energy produced by microscopic marine plants and animals higher in the food chain.
To survive periods when food is scarce, Calanus converts nutrients from its diet into a highly concentrated energy reserve.
Much of that reserve is stored as wax esters.
Scientific analysis of Calanus finmarchicus lipids has demonstrated that these wax esters contain a broad spectrum of fatty acids, including the omega-3 fatty acids EPA, DHA and SDA.1, 3
The wax ester molecule also contains long-chain fatty alcohols. When these alcohols are considered collectively, they are sometimes referred to as marine policosanols.
This means Calanus oil is not simply another source of EPA and DHA. Its lipid composition is structurally different from conventional fish oils.
Wax Ester Omega-3 vs Fish Oil vs Krill Oil
One of the easiest ways to understand wax ester-based omega-3 is to compare the major molecular forms found in marine oils.
Fish oil: Omega-3 fatty acids are generally associated primarily with triglycerides. Some purified and concentrated fish oils use ethyl esters or re-esterified triglycerides.
Krill oil: A substantial portion of the EPA and DHA is associated with phospholipids, although krill oil contains other lipid classes as well.
Calanus oil: Most of the fatty acids are naturally associated with wax esters.
These different molecular structures do not change the fact that EPA is EPA and DHA is DHA. However, the structure in which a fatty acid is delivered can influence how an oil is digested, hydrolyzed, absorbed and metabolized.
That has made Calanus oil an increasingly interesting subject of nutrition research.
Can Humans Absorb Omega-3 Fatty Acids From Wax Esters?
This is an important question.
Historically, wax esters were sometimes assumed to be poorly digested by humans and other mammals. More recent research has demonstrated that this assumption is too simplistic, particularly when wax esters are consumed in appropriate dietary amounts.
A 2016 randomized human study specifically evaluated EPA and DHA delivered in wax ester-rich oil from Calanus finmarchicus.
Eighteen healthy adults consumed Calanus oil providing EPA and DHA primarily in wax ester form. Researchers then measured blood concentrations of EPA and DHA for 72 hours.
The investigators found that both EPA and DHA from the Calanus oil were absorbed and concluded that the wax ester-rich marine oil represented a bioavailable source of EPA and DHA for human consumption. 2
That study answered an important question: omega-3 fatty acids carried in this unusual wax ester structure can indeed become available to the human body.
What Happens With Longer-Term Use?
Researchers have also studied whether regular consumption of Calanus oil can change longer-term omega-3 status.
One study followed older adults participating in an exercise program for 12 weeks. Participants receiving 2 grams of Calanus oil per day increased their Omega-3 Index from approximately 6.1% to 7.4%, while the exercise-only comparison group showed no significant change.4
The Omega-3 Index measures EPA and DHA in red blood cell membranes and is commonly used by researchers as an indicator of longer-term omega-3 status.
An even more informative study was published in 2023.
Researchers at Leibniz University Hannover directly compared:
Calanus oil vs fish oil vs krill oil
for 12 weeks.
Sixty-two participants completed the randomized study. The researchers intentionally provided relatively similar daily quantities of EPA plus DHA among the three groups.
At the end of 12 weeks:
- The Calanus oil group increased its Omega-3 Index by approximately 1.09 percentage points.
- The fish oil group increased approximately 1.00 percentage point.
- The krill oil group increased approximately 1.15 percentage points.
There was no statistically significant difference between the groups.
The researchers concluded that Calanus oil increased long-term omega-3 status to an extent comparable with the fish oil and krill oil tested in the study. 5
This is particularly significant because Calanus oil delivers its fatty acids predominantly through wax esters—a molecular form very different from either conventional fish oil or krill oil.
Are Wax Esters Digested Differently?
Evidence suggests they are.
The ester bond in a wax ester connects a fatty acid to a long-chain fatty alcohol rather than glycerol. This produces a highly hydrophobic molecule with digestive characteristics different from triglycerides.
Laboratory digestion research has found lower or slower release of free fatty acids from wax ester-rich Calanus oils compared with conventional marine oils during simulated gastrointestinal digestion. 6
That does not mean the omega-3s are unavailable.
Human clinical studies clearly demonstrate that EPA and DHA from Calanus oil are bioavailable.2, 4, 5
Instead, the research raises an interesting possibility: wax ester-bound fatty acids may follow a different digestive timeline from conventional triglyceride oils.
Researchers have proposed that slower hydrolysis could influence where in the intestinal tract components of the oil are released.
This area of research is especially interesting because different portions of the gastrointestinal tract contain different nutrient-sensing receptors and metabolic signaling systems.
However, research into the specific physiological consequences of this slower digestion is still developing. Human studies have established omega-3 bioavailability, but claims that wax esters produce specific health effects because they reach a particular portion of the human intestine require additional clinical evidence.
That distinction is important.
More Than EPA and DHA
Another difference between Calanus oil and many highly concentrated omega-3 products is that researchers have identified a broader lipid profile.
Published analyses have reported that Calanus oil naturally contains:
EPA (Eicosapentaenoic Acid)
A long-chain marine omega-3 fatty acid.
DHA (Docosahexaenoic Acid)
Another important long-chain marine omega-3 fatty acid.
SDA (Stearidonic Acid)
An omega-3 fatty acid that serves as an intermediate in the metabolic pathway leading toward EPA.
Long-Chain Monounsaturated Fatty Acids
Including fatty acids such as cetoleic acid and gondoic acid.
Long-Chain Fatty Alcohols
These form the alcohol component of the wax ester molecule and include compounds such as eicosenol and docosenol.
Astaxanthin
A naturally occurring carotenoid pigment that contributes to the characteristic ruby-red color of the oil.
Research therefore increasingly describes Calanus oil not simply as an EPA/DHA supplement, but as a wax ester-rich marine lipid containing multiple naturally occurring lipid components. 1
What Are Marine Policosanols?
The term policosanol generally describes a mixture of long-chain fatty alcohols.
Because a wax ester consists of a fatty acid attached to a fatty alcohol, a wax ester-rich marine oil naturally contains a significant fatty-alcohol component.
Zooca®, the producer of the Calanus oil used in Arctic Ruby Oil, refers to these naturally occurring long-chain alcohols as marine policosanols.
They are not added to the oil as a separate ingredient. They are part of the natural molecular structure of the wax esters produced by Calanus finmarchicus.
Researchers are investigating the biological fate and potential significance of these long-chain fatty alcohols. Published research suggests that fatty alcohols released through wax ester digestion can be absorbed and may subsequently be converted into corresponding fatty acids.
The physiological importance of these compounds in humans remains an active area of study.
Is Calanus Oil the Same Thing as Fish Oil?
No.
Both are marine oils and both can provide EPA and DHA, but their origins and lipid structures are different.
Fish oil is obtained from fish tissue and is dominated by glyceride-based lipids.
Calanus oil is extracted from the marine copepod Calanus finmarchicus and is dominated by wax ester-based lipids.
For that reason, describing Calanus oil simply as another “fish oil” misses one of its defining characteristics.
It represents a different class of naturally occurring marine lipid.
A 2020 scientific review described Calanus oil as the only commercially available marine source of wax esters at the time of publication.7
Where Does Zooca® Calanus® Oil Come From?
The Calanus oil used in Arctic Ruby Oil is supplied by Zooca® / Calanus AS of Norway.
Zooca has spent more than two decades developing methods to harvest and process Calanus finmarchicus from Norwegian waters.
The company developed patented harvesting technology specifically designed for the tiny copepod and processes its Calanus raw material in Norway.
Norway transitioned from experimental harvesting of Calanus finmarchicus to a regulated commercial fishery beginning in 2019. Commercial harvesting is governed by permits, quotas and the country's Marine Resources Act.
Unlike traditional fishing that harvests animals higher in the marine food chain, Calanus finmarchicus occupies a much lower trophic level.
The species is extraordinarily abundant in the Norwegian Sea. Norwegian resource assessments have estimated a standing biomass of approximately 33 million metric tons, while estimates of annual production are substantially larger.
Norwegian authorities nevertheless established conservative commercial harvesting limits as part of an ecosystem-based management program.
What Does This Have to Do With Arctic Ruby Oil?
Arctic Ruby Oil is a wax ester-based marine oil derived from Calanus finmarchicus.
Its omega-3 fatty acids occur within the naturally complex lipid matrix produced by this North Atlantic copepod.
That makes Arctic Ruby Oil fundamentally different from conventional fish-oil and krill-oil supplements.
The important distinction isn't simply how many milligrams of EPA and DHA appear on a label.
It is also how those fatty acids occur in nature.
In Calanus oil, the majority are part of a wax ester-rich marine lipid containing omega-3 fatty acids, long-chain fatty alcohols, monounsaturated fatty acids and naturally occurring astaxanthin.
Human studies have demonstrated that EPA and DHA from this wax ester-rich oil are bioavailable and capable of increasing long-term omega-3 status. 2, 4, 5
Research into the other characteristics of this unusual marine lipid is continuing.
The Bottom Line
Wax ester-based omega-3 oils represent a distinct form of marine nutrition.
Instead of attaching fatty acids primarily to glycerol—as occurs in triglyceride-rich fish oils—a wax ester attaches a fatty acid to a long-chain fatty alcohol.
The North Atlantic copepod Calanus finmarchicus naturally stores much of its energy in this form.
As a result, Calanus oil provides EPA, DHA and SDA within a wax ester-rich lipid matrix that is chemically different from both traditional fish oil and krill oil.
Most importantly, published human research has answered one of the fundamental questions surrounding this unusual lipid structure:
Humans can obtain bioavailable omega-3 fatty acids from wax ester-rich Calanus oil.
A randomized 12-week comparison also found that Calanus oil increased the Omega-3 Index to a similar degree as the fish and krill oils tested when comparable amounts of EPA and DHA were consumed. 5
That combination of unusual chemistry, natural origin and growing human research is why wax ester-based omega-3 oils have become an emerging area of marine nutrition research.
Scientific References
- Schots PC, Pedersen AM, Eilertsen KE, Olsen RL, Larsen TS. “Possible Health Effects of a Wax Ester Rich Marine Oil.” Frontiers in Pharmacology. 2020;11:961. DOI: 10.3389/fphar.2020.00961
- Cook CM, Larsen TS, Derrig LD, Kelly KM, Tande KS. “Wax Ester Rich Oil From the Marine Crustacean, Calanus finmarchicus, is a Bioavailable Source of EPA and DHA for Human Consumption.” Lipids. 2016;51(10):1137–1144. DOI: 10.1007/s11745-016-4189-y
- Pedersen AM, Vang B, Olsen RL. “Lipid Profile of Mice Fed a High-Fat Diet Supplemented With a Wax Ester-Rich Marine Oil.” European Journal of Lipid Science and Technology. 2014;116:1718–1726. DOI: 10.1002/ejlt.201400052
- Wasserfurth P, et al. “Intake of Calanus finmarchicus Oil for 12 Weeks Improves Omega-3 Index in Healthy Older Subjects Engaging in an Exercise Programme.” British Journal of Nutrition. 2020.
- Vosskötter F, Burhop M, Hahn A, Schuchardt JP. “Equal Bioavailability of Omega-3 PUFA From Calanus Oil, Fish Oil and Krill Oil: A 12-Week Randomized Parallel Study.” Lipids. 2023;58(3):129–138. DOI: 10.1002/lipd.12369
- “Comparative Analysis of Fatty Acid Bioaccessibility in Commercial Marine Oil Supplements: An In Vitro Integrated Analytical Study.” Published 2024. Research comparing simulated digestion of fish, krill and Calanus marine oils.
- Gasmi A, et al. “Calanus Oil in the Treatment of Obesity-Related Low-Grade Inflammation, Insulin Resistance, and Atherosclerosis.” Applied Microbiology and Biotechnology. 2020;104(3):967–979. DOI: 10.1007/s00253-019-10293-4