Life Extension Super K
vs
Douglas Laboratories Querciplex
Supplement Comparison

  • Vitamin C: Douglas Laboratories Querciplex has 10× more
  • The image below shows:
    • Side-by-side charts with label nutrient amounts, per serving
    • Nutrient forms as listed on the label
    • 10 nutrients compared
Bar chart: per-serving label amounts and listed forms for Life Extension Super K vs Douglas Laboratories Querciplex.

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Frequently asked questions

Which active ingredients does Life Extension Super K have?

  • Vitamin C appears as Ascorbyl Palmitate
  • Vitamin K appears as Vitamin K1 Phytonadione
  • Vitamin K appears as Vitamin K2 Menaquinone-4 (MK-4)
  • Vitamin K appears as Vitamin K2 trans MK-7 K2VITAL

Which active ingredients does Douglas Laboratories Querciplex have?

  • Vitamin C appears as Ascorbic Acid
  • Quercetin appears as Quercefit Quercetin Phytosome (Sophora japonica extract flower sunflower phospholipid complex)
  • Bromelain appears as Bromelain (Ananas comosus stem)

Which categories do Life Extension Super K and Douglas Laboratories Querciplex belong to?

  • Single Vitamin
  • Antioxidant Complex
  • Herbal Extract

What health concerns do Life Extension Super K and Douglas Laboratories Querciplex address?

  • Heart & Cardiovascular Health
  • Joint & Bone Health
  • Immune System Support
  • Respiratory Health

Which product has a higher amount of Vitamin C per serving?

  • Douglas Laboratories Querciplex has the highest total amount of Vitamin C: 100 mg per serving

How do the serving sizes compare between the two supplements?

  • Serving size:
    • Life Extension Super K: 1 softgel
    • Douglas Laboratories Querciplex: 1 capsule
  • Vitamin C
    • This supplement has 10 mg
    • Recommended Dietary Allowance in men: 90 mg
    • Recommended Dietary Allowance in women: 75 mg
    • Tolerable Upper Intake Level: 2000 mg
  • Vitamin K
    • This supplement has 2600 mcg
    • Adequate Intake in men: 120 mcg
    • Adequate Intake in women: 90 mcg
    • Tolerable Upper Intake Level: Not established
  • Vitamin C
    • This supplement has 100 mg
    • Recommended Dietary Allowance in men: 90 mg
    • Recommended Dietary Allowance in women: 75 mg
    • Tolerable Upper Intake Level: 2000 mg

Last updated: February 12, 2026

  • Sources & Methodology: Nutrient data and forms are taken directly from Supplement Facts labels. Reviewed and standardized by the VIOscan Research Team. Learn more on the Methodology page.
  • We show the Recommended Dietary Allowance (RDA) when available. If no RDA exists, we show the Adequate Intake (AI). Tolerable Upper Intake Levels (UL) are used for upper limits. Unless otherwise noted, RDAs shown correspond to healthy adults aged 19–50 years and are sex-specific. Separate values exist for 51–70 years and >70 years, and pregnancy and lactation are excluded. All values come from the Dietary Reference Intakes (DRIs) published by the National Academies of Sciences, Engineering, and Medicine (NASEM), Food and Nutrition Board (FNB).
  • Transparency: We’re funded by our users. We don’t have sponsors or affiliate links, and we don’t sell supplements.
  • Editorial standards: we provide independent, impartial and objective data analysis.
  • This analysis is for educational purposes only. It is not a substitute for medical advice.
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  • See an error? Report it through our Contact page.
  • Author: VIOscan Research Team