Single-ingredient oral riboflavin,
does it really help with Skin hydration in adults with dry skin?
research showsThe accessible evidence does not establish how much B2 alone changes skin hydration in adults with dry skin. An older hydration trial gave riboflavin butyrate to both groups, while a later B2 trial registered hydration but the accessed main report did not provide a verified hydration result. This establishes neither no effect nor an absence of human research.
ads claimCalling B2 a skin-related nutrient does not establish a hydration gain, onset of benefit or dosage for ordinary adults. No specific advertisement or product was assessed for legal compliance.
Four separate assessment dimensions
| Effect direction and size | Direction and magnitude for B2 alone remain undetermined. Within-arm change on a shared B2 background and an unverified registered outcome are preserved separately. |
|---|---|
| Evidence certainty | A scoped finding that no directly eligible comparative effect was verified in the documented search, not a finding of no effect or global absence of human research. |
| Applicability | Adults with dry skin, single-active oral B2 and stratum-corneum hydration only; not riboflavin butyrate, colon-targeted formulations, mixtures, dietary exposure or animal evidence. |
| Safety | Unknown means that comparative safety for the exact target regimen has not been established, not that harm has been demonstrated. Absence of reported side effects in BES-2B and aggregate events in healthy older adults using colon-targeted capsules do not establish long-term safety of ordinary B2. Pregnancy, children, hepatic/renal disease, concomitant medicines and laboratory interference remain uncharacterized for this question. |
The ? category has no numerical score. The Chamgap measure is not official GRADE or a treatment-success probability.
Useful facts when choosing a product
- The selected question is oral single-ingredient B2.
- The1989 study used riboflavin butyrate; the later study used colon-targeted capsules.
- Study doses describe experiments and are not personal dosing instructions.
Chamgap Semantic Classification Code
Permanent code issued
S.riboflavin.oral-single-active-regimen-unverified.adults-dry-skin-skin-hydration.improve.placebo-background-care-unverifiedSubstances > Riboflavin (vitamin B2) > Oral single-active regimen unverified > Skin hydration in adults with dry skin > Improve > Placebo/background-care comparison unverified
The current value is ?/null because no directly eligible B2-alone comparative effect was identified; shared-B2-background and unverified registered hydration data are not transferred to monotherapy. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.
Exact Claim Classification
These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.
| Intervention class | S · Supplement or nutraceutical |
|---|---|
| Canonical ingredient or intervention | Single-ingredient oral riboflavin (vitamin B2) |
| Source or part used | Isolated chemical: anatomical part not applicable; manufacturing origin unverified |
| Formulation or processing | Single-active oral riboflavin question; salts, derivatives and release profiles not presumed equivalent |
| Route | Oral |
| Dose | No directly eligible regimen established; adjacent BES-2B gave riboflavin butyrate 20 mg/day to both arms |
| Duration | No directly eligible regimen established; adjacent BES-2B lasted four weeks and the colon-targeted trial 12 weeks |
| Population | Adults with dry skin; deficiency correction distinguished from supplementation without confirmed deficiency |
| Effect or condition | Improvement in stratum-corneum hydration |
| Primary endpoint | Between-group stratum-corneum hydration with site and instrument specified |
| Comparator | Proposed placebo/no-B2 with identical background care; no actual directly eligible comparison established |
| Duplicate-detection key | R01|vitamin-B2|oral|SKIN|adults-with-dry-skin |
What the research actually shows
Change in a B2-containing arm is not the same as the comparative effect of B2 itself. BES-2B compared E+B2 with B2, so the between-group contrast concerns E added to B2. Within-arm B2 changes cannot separate treatment from natural change, season or permitted moisturizer use. NCT05803811 differs in formulation/population and its hydration results remain unverified. Human hydration measurements and a registered endpoint exist. The accessible set does not establish a B2-only comparative effect for this page question. Adjacent formulations, combinations, dietary observations and animal data are separated.
Why this is classified as ?
Human hydration data exist, so the no-human-study flag is false. No verified identifying comparative result for the selected B2-only claim supports a truthful confirmatory-replication or bias axis. The bare function returns C on invalid axes, but that is not an accepted grade. The research report is complete; grade and score remain unassigned.
Counterpoint. Current uncertainty does not rule out future directly relevant evidence.
Rejudgment record. Current value based on an unestablished target comparative effect — Supplied stage-zero and axis validation; audit/grading_decision.json
Review performed and remaining limitations
No B2-free comparator or direct effect and CI; registered hydration results and supplements remain unverified. Small nonfacial within-arm arithmetic is not the target effect.
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| BES-2B (1989) skin-hydration trial comparing E+B2 with B2 | Double-blind comparison, but both groups received riboflavin butyrate 20 mg/day for four weeks | 58 enrolled and 47 in efficacy analysis; paired nonfacial hydration data for 11 (7 combination, 4 B2) | A pharmaceutical-company statistician was named; funding and product-manufacture involvement were not fully established | SKIKON-200 skin conductance; no B2-free arm identifies the effect of B2 itself | The randomized contrast tests added vitamin E on a common B2 background; within-arm B2 change is not the target effect | Retained as adjacent human hydration data, not used to score B2-alone efficacy |
| NCT05803811 colon-targeted B2 trial in healthy older adults | 1.4, 10 or 75 mg/day versus placebo for 12 weeks using specialized colon-targeted capsules | 348 enrolled | No funding was reported, while competing-interest disclosures identified six company employees and three people hired by the same company | Skin hydration was registered, but the accessed main report did not provide a verified result | No hydration effect, CI or analysis verified for a dry-skin-selected population | Retained as a registered-outcome gap; not relabelled as no result or no effect |
Receipt — 8 References
Evidence access cutoff: 2026-09-16. Each citation states its actual access level (full-text transcription, abstract, index, or other) and remaining limitations. Bibliographic checking does not certify the study results or treatment efficacy.
Technical integration by: Codex · Evidence date: 2026-09-16 · Corrections: none
Cite this verdict
[Chamgap] Does B2 alone increase hydration in dry skin? — Evidence Grade ?. 8 cited sources checked. Source: https://chamgap.com/en/verdicts/skin-hair/oral-riboflavin-adults-dry-skin-skin-hydration/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.