Bucked Up Buck Naked

Six-dimension breakdown

Why this scored 40/100

Bucked Up Buck Naked is a thermogenic fat-loss formula positioned as 'support fat metabolism, energy levels, and body composition.' The category itself is one of the most evidence-thin in supplements: no over-the-counter thermogenic has cleared the FDA/EMA bar for a fat-loss claim, and meta-analyses of green-tea catechin, capsaicinoid, yohimbine, and caffeine stacks show effect sizes of roughly 1-2% additional weight loss over placebo across 8-12 week studies — clinically small and inconsistent. Bucked Up's fat-burner formulations across their line have historically leaned on proprietary blends with undisclosed per-ingredient doses, which puts specific ingredient dosing behind a marketing wall the label does not open. The 'support fat metabolism' language is careful FDA-safe phrasing but crosses into unverified benefit claim territory when paired with the 'lean physique' marketing. Autofailed on proprietary blend hiding dose (bulk of active matrix in undisclosed blend). Even with disclosed doses, this category rarely earns better than Standard because the underlying mechanism (small metabolic-rate bump plus mild appetite suppression) does not do what fat loss actually requires (caloric deficit and adherence).

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

40 / 100

Tier

Rejected

Category

Supplements

Subcategory

weight metabolic health

Last scored

August 29, 2026

Third-party certifications

None on record at time of scoring

Vendor

Ultimate Sport Nutrition

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.