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#3 in Vitamins Third-Party Tested
Life Extension Super K (90 Softgels)
by Life Extension
"Triple-form vitamin K complex — K1, MK-4, and MK-7 for comprehensive bone and cardiovascular support"
Amazon Rating
4.7/5
Reviews
9,800+
Price Range
$18-24
Servings
90 servings
Non-GMO LE Certified
Our Editorial Rating
9.2
Excellent
Overview
Life Extension Super K provides all three bioactive forms of vitamin K in a single softgel: K1 (phytonadione, 1500mcg), K2 as MK-4 (1000mcg), and K2 as MK-7 (100mcg). This comprehensive approach ensures both short-acting (MK-4) and long-acting (MK-7) K2 activity. Vitamin K is essential for proper calcium metabolism — directing calcium to bones and away from arteries. The 90-softgel count provides a 3-month supply.
Key Ingredients
| Ingredient | Amount |
|---|---|
| Vitamin K1 (Phytonadione) | 1500 mcg |
| Vitamin K2 (MK-4) | 1000 mcg |
| Vitamin K2 (MK-7) | 100 mcg |
Pros & Cons
What We Like
- All 3 forms of vitamin K in one softgel
- 100mcg MK-7 — clinical dose
- 90 softgels = 3-month supply
- 9,800+ reviews, 4.7 stars
- Life Extension research-backed
What Could Be Better
- Contraindicated with blood thinners (warfarin)
- Premium vs single-form K supplements
- Must consult MD if on anticoagulants
- Softgel only — no capsule option
Who Is This For?
Best For
- Bone health optimization
- Those taking vitamin D3
- Cardiovascular calcium management
- Comprehensive K supplementation
Not Ideal For
- Those on warfarin/blood thinners
- Those only needing MK-7
- Budget supplement shoppers
Our Verdict
9.2/10 — Excellent
The most comprehensive vitamin K supplement available. The triple-form approach (K1 + MK-4 + MK-7) covers all bases for calcium metabolism and bone health.