ConsumerLab.com Reveals Major Differences in Nattokinase Supplements: Some Fall Short, Others Overdeliver

White Plains, NY, November 20, 2025 — Nattokinase is a popular enzyme derived from fermented soy and promoted for cardiovascular and circulatory support. However, independent testing by ConsumerLab.com uncovered significant discrepancies between nattokinase supplement label claims and actual potency.

Key Findings:

• Label Accuracy: Out of eight nattokinase supplements tested, only five provided enzyme activity within an acceptable margin of their labeled amounts. Two products delivered far less than claimed, while another product contained substantially more.
• Sub-Potent Products: One supplement delivered less than half its listed nattokinase activity, and another provided only 82% of its labeled activity. In one case, labeling included a footnote implying that the listed enzyme activity applied only “at time of manufacture,” a practice ConsumerLab considers misleading.
• Over-Potent Products: One supplement provided nearly 60% more enzyme activity than stated on its label. While some overage is acceptable to ensure potency through the product’s shelf life, excessive amounts may increase the risk of side effects and make dosing unpredictable.

Prices ranged more than ten-fold—from as little as $0.10 to as much as $1.17 for the same amount of enzyme activity.

“If you take nattokinase, it’s important to choose a product that provides the enzyme activity promised on the label,” said Dr. Tod Cooperman, president of ConsumerLab.com. “Our testing shows that not all supplements deliver what they claim, and a higher price doesn’t necessarily mean better quality.”

ConsumerLab’s Top Pick

Among supplements that passed testing and were Approved for quality, ConsumerLab selected a Top Pick nattokinase supplement that provided its claimed nattokinase activity at a reasonable dose at a good value.

Access the Full Report:

ConsumerLab’s full Nattokinase Supplements Review can now be accessed online by ConsumerLab.com members –currently over 100,000 individual subscribers and thousands more with access through libraries, schools, and medical centers.

The Nattokinase Supplements Review includes test results and comparisons for eight nattokinase supplements selected for testing by ConsumerLab: Allergy Research Group Nattokinase 100 mg, Arthur Andrew Medical Nattovena, Doctor’s Best Nattokinase, Double Wood Supplements Nattokinase 4,000 FU, NOW Nattokinase 100 mg, Nutricost Nattokinase 2,000 FU, Pure Encapsulations NSK-SD 100 mg, and Toku Flow 10,800 FU Nattokinase - Chocolate.

The review summarizes the clinical evidence for and against nattokinase supplementation for specific uses, including reducing the risk of blood clots, lowering blood pressure, cholesterol, and triglyceride levels, and improving memory and cognition or preventing Alzheimer’s disease. It also explains dosage, the best way to take nattokinase, and potential side effects and drug interactions with nattokinase supplements.

A video that explains ConsumerLab’s findings and provides expert tips for selecting and using nattokinase supplements is freely available.

Founded in 1999, ConsumerLab.com is a leading provider of consumer information and independent evaluations of products that affect health and nutrition. It has tested and reviewed over 7,000 products and has published Product Reviews covering nearly every popular category of dietary supplements and health foods.

Membership to ConsumerLab.com is available online and provides immediate access to continually updated reviews of nearly every popular type of dietary supplement and health food, answers to reader questions, and product recalls and warnings. ConsumerLab also provides independent product testing through its voluntary Quality Certification Program. The company is privately held and based in New York. It has no ownership from, or interest in, companies that manufacture, distribute, or sell consumer products.

Nattokinase Supplements Tested | 3 Out of 8 Failed