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90 Veggie Caps DRB-00294
  • Helps support the circulatory system*

  • Helps support the immune system*

  • Non-GMO
  • Gluten Free
  • Vegan
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Suggested Adult Use

Each serving contains 2000 FU of Nattokinase, 40,000 SPU of Serrapeptase enzyme, and 27 mg of Calcium. Take one veggie capsule daily without food.


NSK-SD is simply the trademarked name of the nattokinase enzyme that is produced by Japan BioScience Laboratory.

Doctor's Best is committed to using the highest quality Nattokinase manufactured and independently tested at the industry recognized enzyme manufacturing facility, Deerland Enzymes in Kennesaw, Georgia. Nattokinase is the enzyme present in the food Natto that has been regularly consumed in Japan for centuries. This enzyme does not require “protection” through the stomach, etc. The clinicals have all be conducted as non-enteric coated products.

ALL enzymes are measured in enzymatic units. FU is fibrinolytic units, a measure of enzymatic activity.

The purines are not removed as they are naturally occurring and lower in Doctor's Best Nattokinase than in food.

Natto is produced by a fermentation adding the bacteria Bacillus subtilis to boiled soybeans. The resulting Nattokinase enzyme is produced when Bacillus subtilis acts on the soybeans. While other soy foods contain enzymes, it is only the natto preparation that contains the specific Nattokinase enzyme.

Doctor's Best products can be found at vitamin specialty, chain and independent natural product stores across the country, as well as online. We recommend that you use our online Where to Buy store finder to find a store near you or one of our online partners who can ship to you directly.

Doctor's Best products are quality tested and manufactured in the United States using highly qualified cGMP manufacturers and raw material ingredients. Doctor's Best sources raw materials from around the world and ingredients are subject to the intense testing and verification regardless of geography of origin.