Skin Defense Vitamin D3 + K2

Six-dimension breakdown

Why this scored 60/100

Dermazen Skin Defense Vitamin D3 + K2 is a small DTC brand's implementation of one of the more evidence-supported vitamin combinations in the supplement market. Vitamin D3 (cholecalciferol) is the effective form for correcting the widespread population-level vitamin D deficiency (roughly 40% of US adults meet the clinical insufficiency threshold), with real evidence for bone health, immune function, and possibly modest all-cause mortality benefit at doses achieving 30-50 ng/mL serum 25(OH)D. Vitamin K2 (particularly menaquinone MK-7 form) provides complementary benefit by directing calcium to bone and away from vascular calcification — the pairing is grounded in the vascular-calcification and osteocalcin biochemistry. The 'Skin Defense' branding is a modest reach — D3+K2 is not primarily a skin product, though vitamin D does have real roles in skin health and photodamage response. Product-level transparency (per-serving IU of D3, mcg of K2, form of K2 as MK-4 vs MK-7 which have different half-life profiles) is not fully verifiable at title level. Dermazen is a small DTC brand without USP or NSF third-party certification. Scored Standard reflecting the sound ingredient combination and small-brand transparency limitations.

Evidence & sources

The Vyvata score's Evidence dimension measures the quality of published RCT support for a product's active ingredients at the label dose. Our source hierarchy: double-blind RCTs in MEDLINE-indexed journals > single-blind RCTs > open-label trials > observational studies > mechanism papers > N=1 case studies (anecdotes). Predatory journals and manufacturer-authored studies without independent replication are weighted down.

Product-specific evidence citations for this item are embedded in the analysis text on the "Analysis" tab. For the full framework and evidence hierarchy, see the methodology page.

How to read the Evidence dimension

• 80–100: Multiple double-blind RCTs in indexed journals directly testing this product OR the exact ingredients at the exact dose.
• 60–79: Single double-blind RCT + supporting ingredient literature at the studied dose.
• 40–59: Open-label trials + ingredient literature; no product-specific double-blind evidence.
• 20–39: Ingredient literature only; no product-specific trials or trials in predatory venues.
• 0–19: No credible evidence base or unverifiable claims.

FAQ data has not been generated for this product yet. See the site FAQ for general questions.

Customer reviews

All the data we have on this product

Every VSF-related metafield surfaced verbatim. Nothing hidden. If you spot data that looks wrong, let us know.

VSF score

60 / 100

Tier

Standard

Category

Supplements

Subcategory

vitamins micronutrients

Last scored

August 24, 2026

Third-party certifications

None on record at time of scoring

Vendor

Dermazen

Tags

Dermazen, Shopify Collective

Every score is set from the published rubric, audit-logged, and rescored whenever new evidence emerges (published trials, updated labels, third-party testing releases). Every vendor is scored on the same criteria — no pay-to-play. See our editorial-independence disclosure for the full policy, including brands with an editorial relationship to this site.