CHAMGAP
Verdict No. 3117 · Search date 2026-09-16 · Methodology v1.0

Ordinary thiamine,
does it really help with Handgrip improvement in objectively weak adults?

30-Second Summary
?
Evidence Grade ? · Safety caution
ChatGPT source review and self-verification · Codex technical integration
This is a new independent question. Related verdicts including 162 and 3086 remain unchanged. No image.
The specified 100 mg oral-HCl SmPC reports nausea/vomiting/diarrhea/abdominal pain and hypersensitivity, frequencies unknown; excipient allergy is product-specific. Severe hypersensitivity reports predominantly concern injections. Parenteral anaphylaxis frequencies are not assigned to oral exposure. Dialysis/malabsorption may alter requirements, not establish high-dose oral strength benefit or a safety ceiling. A long-term safe dose for this claim in renal/hepatic impairment is unverified. Alcohol-related deficiency and refeeding require a separate clinical management context. Multi-component refeeding regimens/emergency injections are not evidence for general strength supplementation; this ? assessment is not a reason to stop indicated deficiency treatment. This specific product is not intended for pregnancy/lactation and is not recommended below 3 years; this is not a ban on nutritional thiamine. Adult strength findings cannot be extended to these groups. Age alone diagnoses neither deficiency nor weakness. Furosemide can affect thiamine status and fluorouracil warrants separate review; do not claim an absence of all interactions. No UL reflects insufficient toxicity data. Water solubility/urinary excretion do not guarantee unlimited safety. Study doses are not personal dosing advice.
What the
research shows
Unknown for this specific question. No directly eligible controlled strength result was verified within the recorded search through 16 September 2026. This is not proof of no effect or of no human thiamine research. Deficiency correction, fatigue improvement and derivative/injection findings are different questions.
What the
ads claim
Low TPP, fatigue, uncontrolled CMT follow-up, thiamine derivatives and injections are not substituted for ordinary oral thiamine effects on handgrip in objectively weak adults.

Four separate assessment dimensions

Effect direction and sizeEligible handgrip effect direction and magnitude unverified
Evidence certaintyStage-zero current value because no directly eligible comparison was verified
ApplicabilityObjectively weak adults, oral ordinary thiamine and handgrip only
SafetyCaution, separate from efficacy

? / null, not zero points and not null efficacy

*

Useful facts when choosing a product

  • The page concerns single-ingredient oral ordinary thiamine. Benfotiamine, fursultiamine/TTFD, sulbutiamine, allithiamine, injections and combinations remain separate.
  • Because no directly eligible trial was selected, salt, product, dose, duration, handgrip protocol and principal time remain unverified.
  • Deficiency correction is a separate clinical question, and study exposures are not personal dosing advice.
ID

Chamgap Semantic Classification Code

Permanent code issued

S.thiamine.oral-single-ingredient-form-dose-duration-unverified.objectively-weak-adults-handgrip.improve.placebo-no-added-thiamine-matched-care

Substances > Ordinary thiamine (vitamin B1) > Oral single ingredient with form/dose/duration unverified > Handgrip in objectively weak adults > Improvement > Placebo, no added thiamine or matched care

The current value is ? with a null score. Elderly low-TPP, fatigue, uncontrolled CMT and derivative evidence are not treated as a direct handgrip effect. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.

Download semantic index (JSON) · Codebook v1

Exact Claim Classification

These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.

Intervention classS · Supplement or nutraceutical
Canonical ingredient or interventionOrdinary thiamine (vitamin B1); exact salt unverified
Source or part usedSingle-ingredient source/manufacturer unverified; not whole food
Formulation or processingSingle-ingredient oral product; base/HCl/mononitrate kept separate; no selected verified salt
Routeoral
DoseEligible-study dose unverified
DurationEligible-study treatment duration unverified
PopulationAdults with objectively documented reduced strength; actual cutoff and thiamine status unverified
Effect or conditionWhether objective handgrip improves
Primary endpointOne handgrip endpoint; hand/device/trial rule/units/principal time unverified
ComparatorPlacebo/no added thiamine/otherwise matched usual care
Duplicate-detection keyS|thiamine|oral-single-ingredient-form-dose-duration-unverified|objectively-weak-adults|handgrip-improvement|placebo-no-added-thiamine-matched-care
01

What the research actually shows

Wilkinson (1997) assigned 76 older adults to oral thiamine 10 mg/day or placebo for 3 months and measured dominant-hand grip with a Preston dynamometer. Entry depended on erythrocyte TPP <140 nmol/L, not an objective weakness cutoff. The report describes no significant grip change but gives no quantitative treatment contrast, CI or exact P; it cannot establish no effect. The CMT supplement lists 15 patients, mixing hydrochloride, derivatives, other therapy and a 16-year-old. The Figure 1 HCl grip follow-ups are patients 1 and 3; patient 2 received sulbutiamine. Healthy-marker comparisons were not treated as longitudinal untreated grip controls. The 40-person TARIF crossover used 600–1800 mg/day for 4-week periods separated by a 4-week washout, but fatigue was primary. An indexed nonsignificant grip excerpt does not verify an eligible baseline-weak group or quantitative grip effect. Existing fatigue verdict 3086 remains unchanged. A crossover in 15 students used allithiamine 1 g/day for 5 days and a Biodex System 2 dynamometer, reporting nonsignificant findings (P>0.05). This is derivative/different-population evidence, not proof of null efficacy or equivalence for ordinary thiamine.

02

Why this is classified as ?

No directly eligible controlled oral ordinary-thiamine strength result in objectively weak adults was verified. The current-value instruction requires stage-zero ?/null with downstream axes unscored. The unchanged calculator cannot encode this eligibility/access gap without falsely asserting no human study; its schema errors and raw invalid suggestion are retained, not adopted.

Counterpoint. Wilkinson (1997) assigned 76 older adults to oral thiamine 10 mg/day or placebo for 3 months and measured dominant-hand grip with a Preston dynamometer. Entry depended on erythrocyte TPP <140 nmol/L, not an objective weakness cutoff. The report describes no significant grip change but gives no quantitative treatment contrast, CI or exact P; it cannot establish no effect.

Rejudgment record. No directly eligible controlled handgrip result verified — No directly eligible controlled oral ordinary-thiamine strength result in objectively weak adults was verified. The current-value instruction requires stage-zero ?/null with downstream axes unscored. The unchanged calculator cannot encode this eligibility/access gap without falsely asserting no human study; its schema errors and raw invalid suggestion are retained, not adopted.

Review performed and remaining limitations

Single-assistant ChatGPT self-review

Salt, dose, duration, weakness cutoff, handgrip protocol, comparative effect and CI unverified

03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Wilkinson et al. 1997. The response to treatment of subclinical thiamine deficiency in the elderly.Randomized double-blind placebo-controlled parallel trial stratified by pretreatment TPP76; 38 thiamine and 38 placebo; all completedCanterbury Medical Research Foundation and Sanitarium Health Food Company; product provision not reportedDominant-hand grip with a Preston dynamometer; no baseline low-strength cutoffOral thiamine 10 mg/day for three months was compared with placebo, but no quantitative grip contrast, CI or exact P value was reported. Nonsignificance was not treated as equivalence or no effect.Closest controlled trial but excluded from target-effect grading because objective baseline weakness was not an entry criterion
Bager et al. 2021. High-dose oral thiamine versus placebo for chronic fatigue in quiescent IBD.Randomized double-blind placebo-controlled crossover trial in 40 participants40; grip-specific analyzed denominator unverifiedHealth Research Foundation of Central Denmark Region and Aase and Ejnar Danielsen Foundation; product provision unverifiedFatigue was primary; handgrip was secondary excerpt-level contextThe 600–1,800 mg/day four-week periods did not enroll an objectively weak group, and no quantitative grip effect or CI was verified.Excluded for fatigue-selected population and endpoint mismatch
Artiukhov et al. 2024. Pharmacological doses of thiamine in Charcot–Marie–Tooth neuropathy.Uncontrolled before-after clinical descriptions and biomarker comparisons with mixed HCl, derivatives and other treatments15 in the supplement (14 adults); five adult HCl rows and two verified longitudinal HCl grip casesRussian Foundation for Basic Research and State Task support; product provision unverifiedCMT strength observations and biomarkers; no matched untreated longitudinal handgrip comparisonHCl, sulbutiamine, benfotiamine and other therapies were not pooled and the observations were not converted into a causal between-group handgrip effect.Excluded for uncontrolled design and mixed formulations/ages
Doyle et al. 1997. Allithiamine ingestion does not enhance isokinetic parameters of muscle performance.Placebo-controlled crossover trial in healthy college students using Biodex System 215 healthy college studentsFunding and product supply unverifiedIsokinetic muscle-performance parameters; not handgripNonsignificant findings (P>0.05) after allithiamine 1 g/day for five days do not establish null efficacy or equivalence for ordinary thiamine, objectively weak adults or handgrip.Excluded for derivative, healthy population and different strength endpoint
§

Receipt — 23 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.

Wilkinson et al. 1997. The response to treatment of subclinical thiamine deficiency in the elderly
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Wilkinson 1997 bibliographic record
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Bager et al. 2021. Randomised clinical trial: high-dose oral thiamine versus placebo for chronic fatigue in patients with quiescent inflammatory bowel disease
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Bager 2021 publisher-provided first-page preview
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Artiukhov et al. 2024. Pharmacological Doses of Thiamine Benefit Patients with the Charcot–Marie–Tooth Neuropathy by Changing Thiamine Diphosphate Levels and Affecting Regulation of Thiamine-Dependent Enzymes
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Artiukhov 2024 electronic supplementary materials
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Artiukhov 2024 Russian-language report/figure captions
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Erratum to Artiukhov et al. 2024
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Costantini et al. 2016. High-dose thiamine improves the symptoms of myotonic dystrophy type 1
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Smidt et al. 1991. Influence of Thiamin Supplementation on the Health and General Well-being of an Elderly Irish Population With Marginal Thiamin Deficiency
checked
Nishiyama et al. 1972. Effect of thiamine tetrahydrofurfuryl disulfide (TTFD) on physical fitness chiefly on muscle strength—double blind studies
checked
Doyle et al. 1997. Allithiamine ingestion does not enhance isokinetic parameters of muscle performance
checked
Ohkoshi et al. 2006. Functional Limitations in Thiamine Deficiency Neuropathy: FIM Score Improvement With Treatment
checked
NIH ODS. Thiamin—Health Professional Fact Sheet
checked
Thiamine Hydrochloride 100 mg Tablets—SmPC
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Institute of Medicine 1998. Dietary Reference Intakes, Chapter4: Thiamin
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NICE CG32. Nutrition support for adults
checked
ClinicalTrials.gov NCT03634735
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Bager TARIF family later publications as supplied in prior snapshot3086
checked
Bager et al. 2024. High-dose oral thiamine versus placebo for chronic fatigue in primary biliary cholangitis
checked
2026 B-vitamins/magnesium IBD trial
checked
Thiamine pharmacologic protocols review (evidence map only)
checked
Association of Micronutrients and Handgrip Strength in Korean Adults
checked
Published as a stage-zero current value because no eligible between-group handgrip effect was verified. Deficiency, fatigue, derivatives and uncontrolled observations are not substituted.
Technical integration by: Codex · Evidence date: 2026-09-16 · Corrections: none

Cite this verdict

In adults with objectively documented reduced muscle strength, does single-ingredient oral ordinary thiamine improve handgrip strength versus placebo, no added thiamine or otherwise matched usual care? Evidence Grade ? card
[Chamgap] In adults with objectively documented reduced muscle strength, does single-ingredient oral ordinary thiamine improve handgrip strength versus placebo, no added thiamine or otherwise matched usual care? — Evidence Grade ?. 23 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/oral-thiamine-objectively-weak-adults-handgrip/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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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.