Calanus oil may support heart health in prediabetic women, study shows

New clinical data suggests that Calanus oil supplementation may offer benefits for diastolic function in prediabetic women.¹ Diastolic function can be an indicator of heart failure, the pilot study explains, and Calanus oil is a marine source of long-chain omega-3 polyunsaturated fatty acids, also containing antioxidants such as astaxanthin. The oil, previously studied for potential cardiovascular benefits, is derived from the copepod Calanus finmarchicus, and can be sustainably harvested in the North Atlantic. The Calanus oil used in the study was supplied by Zooca®Lipids. The trial, “Effects of 12 Weeks of Calanus Oil Supplementation on Cardiac Diastolic Function in Obese and Prediabetic Women—A Pilot Study,” was published in Metabolites in September 2025.

Study overview: Calanus oil and heart function in women

For this clinical study, 20 women, aged between 30 and 75, with obesity and prediabetes and no history of heart complications were given eight capsules (4 g) of Calanus oil per day for 12 weeks. The daily dose provided 276 mg EPA and 256 mg DHA, which are associated with cardiovascular benefits. Measurements were taken for systolic and diastolic cardiac function, blood pressure, heart rate (HR), pulse wave velocity (PWV), and for metabolic health metabolic syndrome severity score (Met-S score) and the triacylglycerol glucose–waist-to-height ratio (TyG-WHtR).

The study was conducted at Institute of Food Science and Human Nutrition at Leibniz University Hannover in Germany.

Key findings: improved diastolic function and insulin sensitivity

The main outcome of the study was cardiac diastolic function measured by the E/A ratio (the ratio of the early [E] to late [A] ventricular filling velocities). This measurement assesses heart function through blood flow between heart beats.² Highlighted measurements after 12 weeks of supplementation include:

• E/A was significantly improved from 0.97 to 1.03 (p = 0.023)
• A significant decrease in Met-S score and in TyG-WHtR was seen, which suggested an improvement in metabolic health and enhanced insulin sensitivity
• Central diastolic blood pressure (DBP) decreased (p = 0.047)
• HR decreased (p = 0.048)
• No significant differences were observed in CRP, central systolic BP, or PWV

E/A improvement was associated with the enhanced insulin sensitivity, the researchers noted.

One limitation of the study includes a lack of a placebo group. Ultimately, the researchers concluded that supplementation with Calanus oil could potentially improve diastolic function and have a beneficial effect on metabolic health in prediabetic women.

Potential benefits from Zooca® Calanus oil for prediabetic women

As the study notes, about 589 million adults globally were living with diabetes as of 2024 with estimates reaching about 783 million people by 2045. The press release also noted that women are not as frequently the focus of clinical studies, though are still an important at-risk group.

“These results are encouraging because they point to combined benefits in both cardiac function and metabolic regulation,” stated Marianne Mæhlum, chief marketing and innovation officer at Zooca, in an October press release. “For women with obesity and prediabetes — a group at elevated cardiometabolic risk — finding safe and natural strategies to support long-term health is of great importance. With its unique slow-release composition, Zooca® Calanus® Oil represents a promising nutritional approach to supporting cardiometabolic support during the aging process.”

“What is exciting about this new study is the benefits seen in insulin sensitivity among people with prediabetes, suggesting once more the valuable role of Zooca® Calanus Oil in supporting long-term metabolic health,” added Teresita Rudà, head of marketing and brand positioning at LEHVOSS Nutrition, distributor partners in Europe for Zooca.

References

1. Kerlikowsky, F.; Spahiu, F.; Stöhr, E.J.; Junge, S.; Jonas, W.; Flierdt, E.v.d.; Schuchardt, J.P.; Hahn, A. 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. DOI: 10.3390/metabo15090596.
2. LEHVOSS Nutrition. Zooca® Calanus® Oil Supports Heart and Metabolic Health in New Clinical Study. October 2025.