Description
Source Naturals NSK-SD Nattokinase 200 mg is described by the brand as a whole-body systemic enzyme, isolated from natto, the traditional Japanese soy food, and researched for its role in supporting healthy blood flow by assisting the body's circulatory clearing system. NSK-SD is a specific, clinically studied nattokinase ingredient used across a number of brands, so it is worth checking for this exact designation if you are comparing nattokinase products by ingredient quality rather than brand name alone.
What's in each capsule
Each vegan capsule provides 200 mg of clinically studied NSK-SD nattokinase, standardised to 4,000 FU. The formula is vegan, gluten-free, dairy-free, wheat-free and preservative-free, with no added yeast, egg, sugar, or artificial colours, flavours or fragrance. Other ingredients are microcrystalline cellulose, hydroxypropyl cellulose (capsule), magnesium stearate and silica, and the product contains soya.
Flexible dosing
The label allows for one capsule taken once or twice daily on an empty stomach with 8 ounces of water, rather than a single fixed dose. This means a 60-capsule bottle can last anywhere from one to two months depending on how your healthcare professional recommends you use it, giving more flexibility than a fixed twice-daily formula.
Who this suits
At 4,000 FU per single capsule, this suits people who want a higher-strength dose without needing to take two capsules to reach that FU level. It can also suit people who prefer to adjust their own dose within a labelled range, in consultation with a healthcare professional, rather than following one fixed serving size. The extensive allergen-free list, covering dairy, wheat, egg and preservatives, may also matter if you are choosing a nattokinase supplement for a household managing several dietary restrictions at once.
Who should be cautious
Do not use this product if you have a blood coagulation or blood pressure disorder. Consult your healthcare professional before taking it if you are using any drug that affects blood coagulation or blood pressure, such as prescription vitamin K, heparin, warfarin, diuretics, ACE inhibitors or beta blockers, or if you are pregnant, may become pregnant, or breastfeeding. For more on nattokinase dosing and FU strength, our Nattokinase Benefits, Dosage & Side Effects Guide covers the research in more detail.
Storage
Store in a cool, dry place, and do not use if either tamper-evident seal is broken or missing.
