90 softgels; current manufacturer 3,180 mcg vitamin K · UPC 737870233435
Life Extension Super K is a high-strength option for someone specifically seeking vitamin K1 plus both MK-4 and MK-7 forms of K2. Check the version before buying: Life Extension's current label lists 3,180 mcg of vitamin K per softgel, while HerbsPro's listing shows an older 2,600 mcg formula. Confirm the actual bottle label rather than relying on the product name.
If you take warfarin or a similar vitamin K antagonist, speak with your prescriber before starting, stopping or changing Super K. Vitamin K can interact dangerously with these medicines, so keeping intake consistent matters; this is not a blanket ban on foods containing vitamin K. No upper intake limit has been established for vitamin K, but that does not make a high-strength supplement suitable for everyone.
The HerbsPro listing matches the 90-softgel product and UPC 737870233435, but the shared UPC does not confirm which formula will ship. Ask the seller to confirm the Supplement Facts panel on the actual bottle before ordering.
The current manufacturer label also lists 10 mg of vitamin C as ascorbyl palmitate. Other ingredients include gelatin and beeswax, so this product is not vegan. The manufacturer's directions are one softgel daily with a meal; those directions do not establish that you need this amount.
Vitamin K benefits and limits
Vitamin K supports normal blood clotting and bone-related proteins. Combining K1, MK-4 and MK-7 does not mean three times the benefit, and a higher total amount does not establish better results. The evidence does not establish that this retail blend prevents fractures or reverses arterial calcification, meaning calcium buildup in arteries.
If you want MK-7 alone or a lower vitamin K amount, a different formula fits that goal more closely. That is a difference in formulation, not proof that either option is clinically superior.
Taking vitamin D does not automatically mean you need a vitamin K supplement or this high-strength blend. Our vitamin D alone vs. D3 plus K2 comparison addresses that separate decision.
What is known about independent testing?
No independent laboratory report for a finished lot of this exact Super K formula was verified for this review. That does not establish that the product failed testing. ConsumerLab results for other Life Extension formulas do not verify this product. Our Life Extension brand guide explains why quality needs to be assessed product by product.
Price per labeled serving
On October 15, 2026, HerbsPro listed the 90-softgel bottle at $24 before tax and shipping. At one softgel per labeled serving, $24 divided by 90 is about $0.267 per serving, or 27 cents. This measures cost per serving, not health benefit per dollar. The price belongs to the listing showing the older formula, not a confirmed shipment of the current 3,180 mcg version.
Our editorial assessment
Supplement Explained Score
56/100
Five equally weighted criteria. This is an editorial assessment, not customer stars or a measure of medical effectiveness.
Label clarity 3/5
The current manufacturer lists all three forms and other ingredients, but the same-UPC seller table shows an older 2,600 mcg total. Shipped formula is not confirmed.
Research relevance 3/5
Vitamin K has established nutrient roles. Evidence does not establish that this high-strength three-form retail blend prevents fractures or reverses arterial calcification.
Safety and cautions 3/5
Vitamin K antagonists such as warfarin create a serious interaction context. High strength and gelatin/beeswax also restrict who should choose this formula.
Testing and quality checks 2/5
No independently verified finished-lot potency and contaminant report was found for this exact Super K variant. Reports about other Life Extension formulas do not transfer.
Value for money 3/5
The $24/90 offer is about $0.267 per labeled serving, but its formula-version uncertainty and broad high-strength blend prevent a straightforward value recommendation.
Evaluated from the published Supplement Facts panel, third-party certification records, and clinical references cited below. Unlisted third-party testing lowers the verification score but does not imply contamination.
