NutraBio NAC - 90 Capsules

Six-dimension breakdown

Why this scored 74/100

NutraBio NAC (N-acetyl-cysteine) is a single-ingredient NAC capsule with transparent-label documentation. NAC has one of the better evidence bases in the antioxidant category: as a glutathione precursor, it has RCT support for acetaminophen overdose (FDA-approved indication in IV form), for COPD/bronchitis mucolytic effects at 600-1800 mg/day, and increasingly for oxidative-stress markers and specific inflammatory conditions. Multiple meta-analyses support its effect on glutathione levels and oxidative-stress markers; effect sizes on downstream clinical endpoints are smaller and condition-specific. NutraBio delivers a well-dosed single-ingredient version at 600 or 900 mg per capsule (typical NutraBio format) with published third-party testing. Safety is generally good but not perfect — chronic high-dose NAC can occasionally cause GI discomfort and rarely paradoxical oxidative effects. Note: FDA has periodically challenged NAC's status as a dietary supplement (arguing its 1963 pharmaceutical approval precedes DSHEA), an ongoing regulatory tension that has not affected commercial availability. Solid Verified-tier single-ingredient antioxidant.

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

74 / 100

Tier

Verified

Category

Supplements

Subcategory

immune antioxidants

Last scored

August 29, 2026

Third-party certifications

None on record at time of scoring

Vendor

Ultimate Sport Nutrition

Product type

NutraBio

Tags

Shopify Collective, Ultimate Sport Nutrition

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.