Calanus® Oil (Arctic Zooplankton Omega-3 Wax Esters)

Calanus finmarchicus
Evidence Level
Limited
1 Clinical Trial
3 Documented Benefits
2/5 Evidence Score

Calanus® Oil (made by Calanus AS, Norway, sold under the Zooca brand) is an omega-3 oil from the Arctic copepod Calanus finmarchicus. It provides omega-3 fatty acids (EPA, DHA and stearidonic acid, or SDA) bound as wax esters rather than as the triglycerides found in fish or krill oil. It carries relatively little EPA and DHA per gram: a 4 g daily dose supplied about 276 mg EPA plus 256 mg DHA in the cardiac pilot study. Unlike fish oil or krill oil triglycerides, wax ester-bound omega-3s are absorbed differently and may provide prolonged delivery, unique metabolic effects, and sustainable harvesting advantages. Direct human trials of this oil are small and mostly funded by the manufacturer. A 20-woman uncontrolled pilot with no placebo group reported an improved diastolic filling ratio, lower diastolic blood pressure and lower resting heart rate over 12 weeks, and two randomized placebo-controlled trials in obese adults improved insulin-resistance markers, though glucose-tolerance endpoints such as HbA1c were unchanged.

Studied Dose 2 g/day (capsules); clinical studies 2-4 g/day.
Active Compound Long-chain fatty acid wax esters from Calanus finmarchicus; primary fatty acids EPA (C20:5n-3), SDA (C18:4n-3, stearidonic acid); astaxanthin.

Benefits

Cardiac diastolic function in a small uncontrolled pilot

In a 12-week pilot study, 20 obese prediabetic women took 4 g/day of Calanus oil. Their diastolic filling ratio (E/A) improved from baseline (p = 0.023) and diastolic blood pressure and resting heart rate fell. The study had no placebo group, so the change cannot be attributed to the oil rather than to time or other factors, and the trial was funded by the manufacturer. No independent or placebo-controlled trial has confirmed a cardiac benefit.

Metabolic health in prediabetic populations

In a randomized, placebo-controlled trial, 43 obese adults took 2 g/day of Calanus oil or paraffin placebo for 12 weeks. Fasting insulin, HOMA-IR and a hepatic insulin-resistance index fell significantly, but HbA1c, glucose and insulin during an oral glucose tolerance test, and muscle insulin sensitivity did not change. A larger randomized trial of 266 obese adults with insulin resistance found glucose-homeostasis benefits only in subgroups or when combined with lifestyle changes. Both trials were funded by the manufacturer and reported insulin-resistance indices, not lipid profiles or cytokines.

Sustainable Arctic source with natural astaxanthin

Calanus finmarchicus copepods are the most abundant marine organism on Earth (by biomass), making Calanus® Oil among the most sustainable omega-3 sources available — requiring no fish catch reduction and with a dramatically lower environmental footprint than fish oil. The oil naturally contains a small amount of astaxanthin from the copepod's diet of microalgae, which helps protect the omega-3 fatty acids from oxidation. No human trial of this oil has measured a reduction in inflammation.

Mechanism of action

1

Wax ester omega-3 delivery and membrane integration

Calanus® Oil wax esters (fatty acid + fatty alcohol ester linkage) require pancreatic lipase and cholesterol esterase for hydrolysis — a different digestive pathway than triglyceride omega-3s. This wax ester absorption pathway may provide more gradual, sustained fatty acid release into circulation compared to rapid triglyceride hydrolysis. Once absorbed, EPA from Calanus® Oil incorporates into cell membrane phospholipids, replacing pro-inflammatory arachidonic acid in immune cell membranes and shifting eicosanoid production toward anti-inflammatory resolvins and protectins rather than inflammatory prostaglandins.

Clinical trials

1
Calanus Oil and Cardiac Diastolic Function: Uncontrolled Pilot in 20 Women (No Placebo)
PubMed

Single-arm pilot study: 20 obese prediabetic women took 4 g/day of Calanus oil (276 mg EPA plus 256 mg DHA) for 12 weeks, with no placebo group. Cardiac function was assessed by echocardiography and blood pressure by oscillometry. Funded by Zooca Lipids (Calanus AS), Norway.

20 middle-aged obese women with prediabetes.

The diastolic filling ratio (E/A) improved from baseline (p = 0.023), and diastolic blood pressure and resting heart rate fell. Because there was no placebo group, these within-person changes cannot be attributed to the oil. The trial was funded by the manufacturer. Calanus oil delivers omega-3 as wax esters rich in stearidonic acid, with relatively little EPA and DHA per gram, and its human evidence base is far smaller and weaker than that for fish or krill oil.

Side effects and drug interactions

Common Potential side effects

Generally well tolerated — omega-3 food oil
Fish/shellfish allergy cross-reactivity possible (copepod-derived) — monitor in allergic individuals
Fishy aftertaste possible — take with meals to minimize
Blood thinning effects at high doses — monitor if on anticoagulants

Important Drug interactions

Anticoagulants/antiplatelets — omega-3 fatty acids have mild antiplatelet activity; monitor if on blood thinners
Blood pressure medications — additive blood pressure effects at high omega-3 doses; monitor

Frequently asked questions about Calanus® Oil (Arctic Zooplankton Omega-3 Wax Esters)

What is Calanus Oil?

Calanus® Oil (made by Calanus AS, Norway, sold under the Zooca brand) is an omega-3 oil from the Arctic copepod Calanus finmarchicus. It provides omega-3 fatty acids (EPA, DHA and stearidonic acid, or SDA) bound as wax esters rather than as the triglycerides found in fish or krill oil.

What is Calanus Oil used for?

Calanus Oil is researched primarily for Cardiovascular and Metabolic Health. In a 12-week pilot study, 20 obese prediabetic women took 4 g/day of Calanus oil. Their diastolic filling ratio (E/A) improved from baseline (p = 0.023) and diastolic blood pressure and resting heart rate fell.

What is the recommended dosage of Calanus Oil?

The clinically studied dose is 2 g/day (capsules); clinical studies 2-4 g/day. Always follow the product label and check with a healthcare provider for personal advice.

Is Calanus Oil safe, and does it have side effects?

For most healthy adults, Calanus Oil is well tolerated at studied doses. Reported effects can include: Generally well tolerated — omega-3 food oil Fish/shellfish allergy cross-reactivity possible (copepod-derived) — monitor in allergic individuals It may also interact with some medications. Calanus Oil is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Calanus Oil interact with any medications?

Possible interactions include: Anticoagulants/antiplatelets — omega-3 fatty acids have mild antiplatelet activity; monitor if on blood thinners Blood pressure medications — additive blood pressure effects at high omega-3 doses; monitor If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Calanus Oil?

NutraSmarts rates the evidence for Calanus Oil as Limited (2 out of 5). It is backed by 1 clinical trial and 4 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(4 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Burhop M, Schuchardt JP, Nebl J, et al. Marine Oil from C. finmarchicus Enhances Glucose Homeostasis and Liver Insulin Resistance in Obese Prediabetic Individuals. Nutrients. 2022;14(2)..PubMedUsed to support: Randomized, placebo-controlled trial: 43 obese adults took 2 g/day Calanus oil or paraffin placebo for 12 weeks. Fasting insulin, HOMA-IR and a hepatic insulin-resistance index fell significantly, while HbA1c, oral glucose tolerance test glucose and insulin, and muscle insulin sensitivity were unchanged. Partially funded by the manufacturer (Calanus AS, Norway).
  2. Tauschek L, Røsbjørgen REN, Dalen H, Larsen T, Karlsen T. No Effect of Calanus Oil on Maximal Oxygen Uptake in Healthy Participants: A Randomized Controlled Study. Int J Sport Nutr Exerc Metab. 2022;32(6):468-478..PubMedUsed to support: Double-blind randomized controlled trial: 71 healthy adults took 2 g/day Calanus oil or placebo for 6 months. There was no difference between groups in maximal oxygen uptake (VO2max) or other clinical measures.
  3. Kerlikowsky F, Bartsch M, Jonas W, Hahn A, Schuchardt JP. Calanus Oil and Lifestyle Interventions Improve Glucose Homeostasis in Obese Subjects with Insulin Resistance. Mar Drugs. 2025;23(4):139..PubMedUsed to support: Double-blind, randomized, placebo-controlled 12-week trial in 266 obese adults with insulin resistance comparing 2 g/day, 4 g/day, and 2 g/day plus lifestyle changes against placebo. Improvement in the HOMA index was significant only for 2 g/day plus lifestyle, and for 4 g/day in a subgroup with mild insulin resistance. Funded by Zooca Lipids (Calanus AS), Norway.
  4. Kerlikowsky F, Spahiu F, Stöhr EJ, et al. Effects of 12 Weeks of Calanus Oil Supplementation on Cardiac Diastolic Function in Obese and Prediabetic Women-A Pilot Study. Metabolites. 2025;15(9):596..PubMedUsed to support: Uncontrolled 12-week pilot in 20 obese prediabetic women taking 4 g/day Calanus oil (276 mg EPA plus 256 mg DHA). The E/A diastolic filling ratio improved from baseline (p = 0.023), with lower diastolic blood pressure and resting heart rate, but there was no placebo group, so the changes cannot be attributed to the oil. Funded by Zooca Lipids (Calanus AS), Norway.