Nicotinamide Riboside for Insulin Resistance

Verdict: Does not improve insulin resistance

Human trials consistently show that nicotinamide riboside (NR) does not improve insulin sensitivity or blood-sugar control. Despite encouraging results in mice, every randomized trial in people has come back negative, so NR cannot be recommended for insulin resistance.

D 🔴 D Counter-Evidence Taiwan Regulatory Restriction

🔬Why this grade7-layer evidence engine

This claim earns a D (Counter-Evidence) grade because four randomized, double-blind human trials point the same way: no benefit. The flagship Dollerup 2018 RCT (PMID 29992272; n=40, 2000 mg/day for 12 weeks) used the gold-standard hyperinsulinemic-euglycemic clamp and found no improvement in insulin sensitivity, glucose production, or glucose disposal in obese, insulin-resistant men.

Three further trials corroborate the null result. The same group's 2019 oral-glucose-tolerance study (PMID 31390002) saw no change in glucose tolerance, beta-cell function, or incretin hormones; a 2020 crossover trial (PMID 32320006; n=13) found no effect on whole-body or hepatic insulin sensitivity; and a 2025 pilot in childhood-cancer survivors (PMID 39387327; n=20) showed no between-arm difference in glucose-homeostasis markers. A strong signal in obese, diabetic mice simply did not translate to humans.

Regulators address only safety, not efficacy: the US FDA accepted NR as GRAS and EFSA cleared it as a niacin source, but neither endorses it for blood sugar. No major clinic or medical society (NIH ODS, Mayo, Cleveland Clinic, Harvard) recommends NR for this use. Trials were short and small and none enrolled diagnosed type 2 diabetics, but four consistently negative RCTs make a future benefit unlikely. Note that NR should not be confused with NMN, a different compound.

⚖️

Scoring transparency

All scores computed by a 7-layer evidence engine — fully auditable

Raw score 0.54

← counter-evidence / ineffectiveeffective / strong evidence →

Final grade

D · Taiwan Regulatory Restriction

Confidence

77%

Broadly consistent

Evidence level

Multiple smaller RCTs (n<500)

How strongly each layer supports this effect

lower = less supportive

L11 AI re-checkIndependent read

0.30

L1 ExamineGlobal benchmark

0.50

L3 MechanismPlausibility

0.50

L5 Clinical bodiesAuthoritative stance

0.50

L2 PubMedPrimary literature

0.70

Against Mixed Supports

▸View the full decision path (audit trail)

compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.54
tier_from_score — 依分數區間映射至 tier letter
apply_hec_rules — 無高階證據可裁決
tier_strict_requirement_check — | C→D 因 scope.conflation_risk=true 且 L11 獨評較低 (B7-2 tier cap)
detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
decide_status — 依 tier + dispute 結果決定 status

📄PubMed studies (4)L2 · primary research & systematic reviews

A randomized placebo-controlled clinical trial of nicotinamide riboside in obese men: safety, insulin-sensitivity, and lipid-mobilizing effects

PMID: 29992272 2018 RCT (double-blind) n = 40

Finding: NR was safe and well-tolerated, but insulin sensitivity, endogenous glucose production, and glucose disposal and oxidation were not improved versus placebo in obese, insulin-resistant men. No effect on resting energy expenditure or lipid oxidation. This is the Dollerup 2018 trial.

Government Effect size: NULL — no significant between-group difference in clamp-derived insulin sensitivity

View on PubMed

Effects of Nicotinamide Riboside on Endocrine Pancreatic Function and Incretin Hormones in Nondiabetic Men With Obesity

PMID: 31390002 2019 RCT (double-blind) n = 40

Finding: NR produced no significant changes in fasting or postprandial glucose, insulin, or C-peptide; beta-cell function, glucagon, and incretin (GLP-1, GIP) responses did not respond to the intervention; overall glucose tolerance and insulin sensitivity unchanged.

Academic Effect size: NULL — no change in glucose tolerance or pancreatic/incretin function

View on PubMed

Nicotinamide riboside supplementation alters body composition and skeletal muscle acetylcarnitine concentrations in healthy obese humans

PMID: 32320006 2020 RCT (double-blind) n = 13

Finding: No effect of NR on whole-body insulin-stimulated glucose uptake or hepatic insulin sensitivity, and no effect on mitochondrial function. NR did increase fat-free mass percentage, sleeping metabolic rate, and muscle acetylcarnitine, but these did not translate to improved insulin sensitivity.

🟠 Limited quality Effect size: NULL — no difference in whole-body or hepatic insulin sensitivity

View on PubMed

Feasibility of telehealth exercise and nicotinamide riboside supplementation in survivors of childhood cancer at risk for diabetes: A pilot randomized controlled trial

PMID: 39387327 2025 隨機對照試驗 n = 20

Finding: Feasibility endpoints were met. Secondary endpoints, including glucose-homeostasis biomarkers, were not significantly different between study arms at completion.

🟠 Limited quality Effect size: NULL — no significant between-arm difference in glucose homeostasis (pilot, underpowered)

View on PubMed

🏛️Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …

L4a US FDA

Supportive

Based on the information provided by ChromaDex, Inc., as well as other information available to FDA, the agency has no questions at this time regarding ChromaDex, Inc.'s conclusion that nicotinamide riboside chloride is GRAS under the intended conditions of use. source↗

L4b EU EFSA

Supportive

L5a NIH Office of Dietary Supplements

Cautious

L5c Cleveland Clinic

Not addressed

L5e Specialty Society (condition-mapped)

Not addressed

✓PMID 100% verifiedevery citation checked via NCBI Entrez

🔬4 PubMed studiesindependently re-checked by multiple sub-agents

engine_version: v1.0 claim_id: CLM-COND-insulin-resistance-INT-nicotinamide-riboside-001 繁體中文版 →