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Dr. Grey AI

Supplement

Niacin (Vitamin B3)

Niacin is vitamin B3, a nutrient your cells use to make molecules that carry energy. People mostly look at it for high cholesterol, where the evidence is moderate, and in one trial of people with low HDL on statins, apolipoprotein A, HDL's main protein, went up. Large studies found no clear difference in deaths overall or from heart disease, though, so heart benefits remain unproven.

Sources: PMID 22085343

Best evidence
Grade B
Conditions studied
12
Outcomes
117
Graded outcomes
0154

Evidence by condition

  • Strong
  • Moderate
  • Limited
  • Very limited

12 conditions

Metabolic Health

Metabolic Health: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Adiponectin

Moderate Increase

Improves (the measure goes up)Moderate effect1 study288 people

Studies that measured adiponectin

Adrenaline

No effect

NoneNo effect12 people
InsulinChanges; see studies2 studies160 people

Studies that measured insulin

Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies37 people

Studies that measured low-density lipoprotein (ldl)

Total cholesterolImproves (the measure goes down)2 studies30 people

Studies that measured total cholesterol

Apolipoprotein AImproves (the measure goes up)1 study30 people
Blood glucoseImproves (the measure goes down)1 study103 people
High-density lipoprotein (HDL)Improves (the measure goes up)1 study37 people
Ketone BodiesImproves (the measure goes up)1 study12 people
Blood FlowImproves (the measure goes up)37 people
Blood PressureImproves (the measure goes down)7 people
Body FatImproves (the measure goes down)7 people
C-Reactive Protein (CRP)Improves (the measure goes down)616 people
Cell Adhesion FactorsImproves (the measure goes down)30 people
CortisolImproves (the measure goes down)12 people
Fat OxidationImproves (the measure goes up)7 people
GlucagonChanges; see studies12 people
Glycemic ControlImproves (the measure goes up)46 people
Interleukin 6Improves (the measure goes down)30 people
LeptinImproves (the measure goes up)165 people
Liver EnzymesChanges; see studies30 people
Metabolic RateImproves (the measure goes up)7 people
Plasma NitrateImproves (the measure goes up)7 people
ResistinImproves (the measure goes up)30 people
TNF-AlphaImproves (the measure goes down)30 people
TriglyceridesImproves (the measure goes down)37 people
WeightImproves (the measure goes down)7 people

Nonalcoholic Fatty Liver Disease (NAFLD)

Nonalcoholic Fatty Liver Disease (NAFLD): outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Apolipoprotein B

Small Improvement

Improves (the measure goes down)Small effect3 studies27 people

Studies that measured apolipoprotein b

InsulinChanges; see studies2 studies27 people

Studies that measured insulin

Blood glucoseImproves (the measure goes down)1 study27 people

Studies that measured blood glucose

Body FatImproves (the measure goes down)27 people
Glycemic ControlImproves (the measure goes up)27 people
TriglyceridesImproves (the measure goes down)27 people
vLDL-CImproves (the measure goes down)27 people
WeightImproves (the measure goes down)27 people

Obesity

  • Adiponectin: improves
  • Apolipoprotein B: improves
  • Insulin: changes; see studies
Obesity: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Adiponectin

Moderate Increase

Improves (the measure goes up)Moderate effect1 study9 people

Studies that measured adiponectin

Apolipoprotein BImproves (the measure goes down)3 studies27 people

Studies that measured apolipoprotein b

InsulinChanges; see studies2 studies36 people

Studies that measured insulin

Blood glucoseImproves (the measure goes down)1 study36 people

Studies that measured blood glucose

Body FatImproves (the measure goes down)27 people
Glycemic ControlImproves (the measure goes up)36 people
TriglyceridesImproves (the measure goes down)27 people
vLDL-CImproves (the measure goes down)27 people
WeightImproves (the measure goes down)27 people

Dyslipidemia

  • Apolipoprotein A: improves
  • Apolipoprotein B: improves
  • Low-density lipoprotein (LDL): improves
Dyslipidemia: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Apolipoprotein A

Small Increase

Improves (the measure goes up)Small effect1 study157 people

Studies that measured apolipoprotein a

Apolipoprotein BImproves (the measure goes down)3 studies157 people

Studies that measured apolipoprotein b

Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies18 people

Studies that measured low-density lipoprotein (ldl)

Total cholesterolImproves (the measure goes down)2 studies139 people

Studies that measured total cholesterol

Blood glucoseImproves (the measure goes down)1 study18 people

Studies that measured blood glucose

High-density lipoprotein (HDL)Improves (the measure goes up)1 study157 people
BilirubinChanges; see studies18 people
Blood FlowImproves (the measure goes up)18 people
C-Reactive Protein (CRP)Improves (the measure goes down)18 people
TriglyceridesImproves (the measure goes down)157 people

Atherosclerosis

  • Apolipoprotein A: improves
  • Apolipoprotein B: improves
  • Low-density lipoprotein (LDL): improves
Atherosclerosis: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Apolipoprotein A

Small Increase

Improves (the measure goes up)Small effect1 study3,196 people

Studies that measured apolipoprotein a

Apolipoprotein BImproves (the measure goes down)3 studies3,196 people

Studies that measured apolipoprotein b

Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies3,196 people

Studies that measured low-density lipoprotein (ldl)

High-density lipoprotein (HDL)Improves (the measure goes up)1 study3,196 people

Studies that measured high-density lipoprotein (hdl)

Heart Attack RiskChanges; see studies3,196 people
Stroke RiskChanges; see studies3,196 people
TriglyceridesImproves (the measure goes down)3,196 people

Weight Loss & Maintenance

  • Adiponectin: improves
  • Insulin: changes; see studies
  • Low-density lipoprotein (LDL): improves
Weight Loss & Maintenance: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Adiponectin

Moderate Increase

Improves (the measure goes up)Moderate effect1 study30 people

Studies that measured adiponectin

InsulinChanges; see studies2 studies30 people

Studies that measured insulin

Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies30 people

Studies that measured low-density lipoprotein (ldl)

Total cholesterolImproves (the measure goes down)2 studies30 people

Studies that measured total cholesterol

Apolipoprotein AImproves (the measure goes up)1 study30 people

Studies that measured apolipoprotein a

Blood glucoseImproves (the measure goes down)1 study30 people
High-density lipoprotein (HDL)Improves (the measure goes up)1 study30 people
Blood FlowImproves (the measure goes up)30 people
C-Reactive Protein (CRP)Improves (the measure goes down)30 people
Cell Adhesion FactorsImproves (the measure goes down)30 people
Glycemic ControlImproves (the measure goes up)30 people
Interleukin 6Improves (the measure goes down)30 people
LeptinImproves (the measure goes up)30 people
Liver EnzymesChanges; see studies30 people
ResistinImproves (the measure goes up)30 people
TNF-AlphaImproves (the measure goes down)30 people
TriglyceridesImproves (the measure goes down)30 people

General Cardiovascular Health

  • All-Cause Mortality
  • Apolipoprotein B: improves
  • Low-density lipoprotein (LDL): improves
General Cardiovascular Health: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
All-Cause Mortality

No effect

NoneNo effect1 study35,543 people

Studies that measured all-cause mortality

Apolipoprotein BImproves (the measure goes down)3 studies5,470 people

Studies that measured apolipoprotein b

Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies11,272 people

Studies that measured low-density lipoprotein (ldl)

Total cholesterolImproves (the measure goes down)2 studies5,149 people

Studies that measured total cholesterol

Apolipoprotein AImproves (the measure goes up)1 study5,489 people

Studies that measured apolipoprotein a

Blood glucoseImproves (the measure goes down)1 study3,847 people
Cardiovascular Disease MortalityImproves (the measure goes down)1 study32,966 people
High-density lipoprotein (HDL)Improves (the measure goes up)1 study11,147 people
Gastrointestinal symptomsImproves (the measure goes down)35,353 people
HeadachesImproves (the measure goes down)300 people
Heart Attack RiskChanges; see studies34,829 people
ItchingImproves (the measure goes up)5,800 people
Stroke RiskChanges; see studies33,661 people
TriglyceridesImproves (the measure goes down)4,546 people

Coronary Artery Disease (CAD)

  • Cardiovascular Disease Mortality
  • Total cholesterol: improves
  • Heart Attack Risk: changes; see studies
Coronary Artery Disease (CAD): outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Cardiovascular Disease Mortality

No effect

NoneNo effect1 study2,840 people

Studies that measured cardiovascular disease mortality

Total cholesterolImproves (the measure goes down)2 studies2,840 people

Studies that measured total cholesterol

Heart Attack RiskChanges; see studies2,840 people
TriglyceridesImproves (the measure goes down)2,840 people

Cardiovascular Disease

  • Cardiovascular Disease Mortality
  • Major Adverse Cardiac Events: changes; see studies
  • Stroke Risk: changes; see studies
Cardiovascular Disease: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Cardiovascular Disease Mortality

No effect

NoneNo effect1 study35,760 people

Studies that measured cardiovascular disease mortality

Major Adverse Cardiac EventsChanges; see studies4,364 people
Stroke RiskChanges; see studies16,705 people

High Cholesterol

  • Low-density lipoprotein (LDL): improves
  • High-density lipoprotein (HDL): improves
  • Glycemic Control: worsens
High Cholesterol: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies20 people

Studies that measured low-density lipoprotein (ldl)

High-density lipoprotein (HDL)Improves (the measure goes up)1 study20 people

Studies that measured high-density lipoprotein (hdl)

Glycemic Control

Small Detriment

Worsens (the measure goes down)Small effect20 people
Hepatic Glucose ProductionChanges; see studies20 people
TriglyceridesImproves (the measure goes down)20 people
vLDL-CImproves (the measure goes down)20 people

Type 2 Diabetes

  • Low-density lipoprotein (LDL): improves
  • Total cholesterol: improves
  • Blood glucose: worsens
Type 2 Diabetes: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies988 people

Studies that measured low-density lipoprotein (ldl)

Total cholesterolImproves (the measure goes down)2 studies958 people

Studies that measured total cholesterol

Blood glucose

Small Detriment

Worsens (the measure goes up)Small effect1 study1,273 people

Studies that measured blood glucose

High-density lipoprotein (HDL)Improves (the measure goes up)1 study1,082 people

Studies that measured high-density lipoprotein (hdl)

HbA1cImproves (the measure goes down)220 people
TriglyceridesImproves (the measure goes down)988 people

Metabolic Syndrome

  • Low-density lipoprotein (LDL): improves
  • High-density lipoprotein (HDL): improves
  • Glycemic Control: worsens
Metabolic Syndrome: outcomes studied for Niacin (Vitamin B3)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Low-density lipoprotein (LDL)Improves (the measure goes down)2 studies20 people

Studies that measured low-density lipoprotein (ldl)

High-density lipoprotein (HDL)Improves (the measure goes up)1 study20 people

Studies that measured high-density lipoprotein (hdl)

Glycemic Control

Small Detriment

Worsens (the measure goes down)Small effect20 people
Hepatic Glucose ProductionChanges; see studies20 people
TriglyceridesImproves (the measure goes down)20 people
vLDL-CImproves (the measure goes down)20 people

Key findings

  • AdiponectinMetabolic HealthImproves (the measure goes up)
  • Apolipoprotein BNonalcoholic Fatty Liver Disease (NAFLD)Improves (the measure goes down)
  • Apolipoprotein ADyslipidemiaImproves (the measure goes up)

Shop the evidence-backed picks

Third-party tested Niacin (Vitamin B3) products, in the forms the graded studies used where we can match them.

  • Grade B

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Studies cited

17 studies from PubMed

  1. Effects of NAD+ precursor supplementation on glucose and lipid metabolism in humans: a meta-analysisNutr Metab · PMID 35303905
  2. Extended-release niacin raises adiponectin and leptinAtherosclerosis · PMID 16887123
  3. Effects of nicotinic acid on insulin sensitivity and blood pressure in healthy subjectsJ Hum Hypertens · PMID 10980588
  4. The effects of free fatty acids on gluconeogenesis and glycogenolysis in normal subjectsJ Clin Invest · PMID 9927497
  5. Impaired beta-cell function in human aging: response to nicotinic acid-induced insulin resistanceJ Clin Endocrinol Metab · PMID 16757523
  6. Relationship between Changes in Plasma Adiponectin Concentration and Insulin Sensitivity after Niacin TherapyCardiorenal Med · PMID 22969777
  7. The effect of niacin on inflammatory markers and adipokines: a systematic review and meta-analysis of interventional studies.Eur J Nutr · PMID 38761279
  8. Short-term effects of extended-release niacin with and without the addition of laropiprant on endothelial function in individuals with low HDL-C: a randomized, controlled crossover trialClin Ther · PMID 24768191
  9. Niacin, but not gemfibrozil, selectively increases LP-AI, a cardioprotective subfraction of HDL, in patients with low HDL cholesterolArterioscler Thromb Vasc Biol · PMID 11701466
  10. Clofibrate and niacin in coronary heart diseaseJAMA · PMID 1088963
  11. Nicotinic acid effects on insulin sensitivity and hepatic lipid metabolism: an in vivo to in vitro studyHorm Metab Res · PMID 24806747
  12. Niacin in patients with low HDL cholesterol levels receiving intensive statin therapyN Engl J Med · PMID 22085343
  13. Effect of fenofibrate and niacin on intrahepatic triglyceride content, very low-density lipoprotein kinetics, and insulin action in obese subjects with nonalcoholic fatty liver diseaseJ Clin Endocrinol Metab · PMID 20371660
  14. Niacin for primary and secondary prevention of cardiovascular events.Cochrane Database Syst Rev · PMID 28616955
  15. Effects of niacin on apo A1 and B levels: a systematic review and meta-analysis of randomised controlled trials.Br J Nutr · PMID 38112076
  16. Supplemental Vitamins and Minerals for Cardiovascular Disease Prevention and Treatment: JACC Focus SeminarJ Am Coll Cardiol · PMID 33509399
  17. Effectiveness of niacin supplementation for patients with type 2 diabetes: A meta-analysis of randomized controlled trialsMedicine · PMID 32702899

Protocols that include Niacin (Vitamin B3)