Supplement

Betaine

Betaine is a nutrient found in beets and grains that acts as a methyl donor, helping the liver process homocysteine and fat. People mostly look at it for nonalcoholic steatohepatitis, where liver enzymes improved with moderate evidence, and betaine-containing toothpaste and mouthwash also eased dry mouth symptoms and increased saliva. Still, the liver finding came from about 30 people, while blood sugar, blood flow, and athletic performance studies found no clear difference.

Sources: PMID 12761586; PMID 21950587

Updated 8 November 2026
How we grade
21 studies cited

Best evidence: Grade B
Conditions studied: 17
Outcomes: 148
Graded outcomes: 03313

Evidence by condition

Strong
Moderate
Limited
Very limited

17 conditions

Dry Mouth

Dry Mouth: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Salivation Small Increase	Improves (the measure goes up)	Small effect	3 studies	143 people
Studies that measured salivation Evaluation of the clinical efficacy of a betaine-containing mouthwash and an intraoral device for the treatment of dry mouthJ Oral Pathol Med · PMID 21950587 Safety and effectiveness of topical dry mouth products containing olive oil, betaine, and xylitol in reducing xerostomia for polypharmacy-induced dry mouthJ Oral Rehabil · PMID 17824884 Betaine-containing toothpaste relieves subjective symptoms of dry mouthActa Odontol Scand · PMID 9669455
	Dry Mouth Symptoms Small Improvement	Improves (the measure goes down)	Small effect	1 study	45 people
Studies that measured dry mouth symptoms Effects of a betaine-containing toothpaste on subjective symptoms of dry mouth: a randomized clinical trialJ Contemp Dent Pract · PMID 12761586

Nonalcoholic Steatohepatitis (NASH)

Nonalcoholic Steatohepatitis (NASH): outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Liver Enzymes Small Improvement	Improves (the measure goes down)	Small effect		30 people
	Liver Fibrosis	Changes; see studies		1 study	30 people
Studies that measured liver fibrosis Betaine, a promising new agent for patients with nonalcoholic steatohepatitis: results of a pilot studyAm J Gastroenterol · PMID 11569700
	Liver Fat	Changes; see studies			30 people

Metabolic Syndrome

Apolipoprotein A: improves
Homocysteine: changes; see studies
Serum Cobalamin: improves

Metabolic Syndrome: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Apolipoprotein A Small Increase	Improves (the measure goes up)	Small effect		27 people
	Homocysteine	Changes; see studies		4 studies	61 people
Studies that measured homocysteine Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjectsAm J Clin Nutr · PMID 12399266 Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humansJ Nutr · PMID 16365055 Betaine supplementation and plasma homocysteine in healthy volunteersArch Intern Med · PMID 10979070 Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in malesNutr Metab Cardiovasc Dis · PMID 19346114
	Serum Cobalamin	Improves (the measure goes up)		2 studies	34 people
Studies that measured serum cobalamin The effect of low doses of betaine on plasma homocysteine in healthy volunteersBr J Nutr · PMID 15522136 Betaine supplementation lowers plasma homocysteine in healthy men and womenJ Nutr · PMID 12730412
	Fibrinogen	Improves (the measure goes up)		1 study	27 people
Studies that measured fibrinogen Long-term effect of betaine on risk factors associated with the metabolic syndrome in healthy subjectsEur J Clin Nutr · PMID 20978525
	Total cholesterol	Changes; see studies		1 study	27 people
Studies that measured total cholesterol Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humansPLoS Med · PMID 15916468
	High-density lipoprotein (HDL)
	LDL Oxidation	Changes; see studies			27 people
	Liver Enzymes	Changes; see studies			27 people
	Low-density lipoprotein (LDL)	Changes; see studies			27 people
	Plasminogen Inhibitor-1	Improves (the measure goes up)			27 people
	Serum Folate	Improves (the measure goes up)			34 people

Coronary Artery Disease (CAD)

Apolipoprotein A: improves
Homocysteine: changes; see studies
Fibrinogen: improves

Coronary Artery Disease (CAD): outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Apolipoprotein A Small Increase	Improves (the measure goes up)	Small effect		27 people
	Homocysteine	Changes; see studies		4 studies	27 people
Studies that measured homocysteine Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjectsAm J Clin Nutr · PMID 12399266 Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humansJ Nutr · PMID 16365055 Betaine supplementation and plasma homocysteine in healthy volunteersArch Intern Med · PMID 10979070 Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in malesNutr Metab Cardiovasc Dis · PMID 19346114
	Fibrinogen	Improves (the measure goes up)		1 study	27 people
Studies that measured fibrinogen Long-term effect of betaine on risk factors associated with the metabolic syndrome in healthy subjectsEur J Clin Nutr · PMID 20978525
	Total cholesterol	Changes; see studies		1 study	27 people
Studies that measured total cholesterol Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humansPLoS Med · PMID 15916468
	High-density lipoprotein (HDL)
	LDL Oxidation	Changes; see studies			27 people
	Liver Enzymes	Changes; see studies			27 people
	Low-density lipoprotein (LDL)	Changes; see studies			27 people
	Plasminogen Inhibitor-1	Improves (the measure goes up)			27 people

High Cholesterol

Apolipoprotein A: improves
Homocysteine: changes; see studies
Fibrinogen: improves

High Cholesterol: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Apolipoprotein A Small Increase	Improves (the measure goes up)	Small effect		27 people
	Homocysteine	Changes; see studies		4 studies	27 people
Studies that measured homocysteine Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjectsAm J Clin Nutr · PMID 12399266 Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humansJ Nutr · PMID 16365055 Betaine supplementation and plasma homocysteine in healthy volunteersArch Intern Med · PMID 10979070 Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in malesNutr Metab Cardiovasc Dis · PMID 19346114
	Fibrinogen	Improves (the measure goes up)		1 study	27 people
Studies that measured fibrinogen Long-term effect of betaine on risk factors associated with the metabolic syndrome in healthy subjectsEur J Clin Nutr · PMID 20978525
	Total cholesterol	Changes; see studies		1 study	27 people
Studies that measured total cholesterol Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humansPLoS Med · PMID 15916468
	High-density lipoprotein (HDL)
	LDL Oxidation	Changes; see studies			27 people
	Liver Enzymes	Changes; see studies			27 people
	Low-density lipoprotein (LDL)	Changes; see studies			27 people
	Plasminogen Inhibitor-1	Improves (the measure goes up)			27 people

General Athletic Performance

Anaerobic Capacity
Blood glucose
Power Output

General Athletic Performance: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Anaerobic Capacity No effect		NoneNo effect		34 people
	Blood glucose No effect		NoneNo effect		34 people
	Power Output Mixed effect			4 studies
Studies that measured power output Effect of betaine supplementation on power performance and fatigueJ Int Soc Sports Nutr · PMID 19250531 Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performanceAmino Acids · PMID 21744011 The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained menJ Strength Cond Res · PMID 22080324 Ergogenic effects of betaine supplementation on strength and power performanceJ Int Soc Sports Nutr · PMID 20642826
	IGF-1	Improves (the measure goes up)		1 study	12 people
Studies that measured igf-1 Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exerciseEur J Appl Physiol · PMID 22976217
	Oxygen Uptake	Improves (the measure goes up)		1 study	10 people
Studies that measured oxygen uptake Influence of betaine consumption on strenuous running and sprinting in a hot environmentJ Strength Cond Res · PMID 18438230
	Blood Lactate (Exercise)	Changes; see studies			37 people
	Body Fat
	Cortisol	Changes; see studies			12 people
	Fatigue Symptoms	Changes; see studies			35 people
	Growth Hormone	Improves (the measure goes up)			12 people
	Heart Rate	Changes; see studies			23 people
	Hematocrit	Improves (the measure goes up)			22 people
	Hydration (Total Body Water)	Improves (the measure goes up)			22 people
	Insulin	Changes; see studies			12 people
	Muscle Creatine Content	Improves (the measure goes up)			34 people
	Muscle Mass
	Muscle Oxygenation	Improves (the measure goes up)			13 people
	Muscle Soreness	Changes; see studies			24 people
	Muscular Endurance
	Nitric Oxide	Improves (the measure goes up)			13 people
	Oxidative Stress Biomarkers	Changes; see studies			13 people
	Rating of Perceived Exertion	Improves (the measure goes up)			47 people
	Training Volume	Improves (the measure goes up)			13 people
	Weight

Metabolic Health

Blood glucose

Metabolic Health: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Blood glucose No effect		NoneNo effect		42 people

Muscle Size Strength

Anaerobic Capacity

Muscle Size Strength: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Anaerobic Capacity No effect		NoneNo effect		24 people

General Cardiovascular Health

Blood Flow

General Cardiovascular Health: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Blood Flow No effect		NoneNo effect		39 people

Running Performance

Anaerobic Capacity
Power Output
Oxygen Uptake: improves

Running Performance: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Anaerobic Capacity No effect		NoneNo effect		26 people
	Power Output Mixed effect			4 studies
Studies that measured power output Effect of betaine supplementation on power performance and fatigueJ Int Soc Sports Nutr · PMID 19250531 Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performanceAmino Acids · PMID 21744011 The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained menJ Strength Cond Res · PMID 22080324 Ergogenic effects of betaine supplementation on strength and power performanceJ Int Soc Sports Nutr · PMID 20642826
	Oxygen Uptake	Improves (the measure goes up)		1 study	10 people
Studies that measured oxygen uptake Influence of betaine consumption on strenuous running and sprinting in a hot environmentJ Strength Cond Res · PMID 18438230
	Blood glucose
	Body Fat
	Heart Rate	Changes; see studies			10 people
	Hematocrit	Improves (the measure goes up)			10 people
	Hydration (Total Body Water)	Improves (the measure goes up)			10 people
	Muscle Mass
	Rating of Perceived Exertion	Improves (the measure goes up)			10 people
	Weight

Nonalcoholic Fatty Liver Disease (NAFLD)

Adiponectin
Liver Fibrosis: changes; see studies
Liver Enzymes: changes; see studies

Nonalcoholic Fatty Liver Disease (NAFLD): outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Adiponectin No effect		NoneNo effect		34 people
	Liver Fibrosis	Changes; see studies		1 study	34 people
Studies that measured liver fibrosis Betaine, a promising new agent for patients with nonalcoholic steatohepatitis: results of a pilot studyAm J Gastroenterol · PMID 11569700
	Liver Enzymes	Changes; see studies			34 people
	Liver Fat	Changes; see studies			34 people
	TNF-Alpha	Changes; see studies			34 people
	Weight

Obesity

Blood glucose
Homocysteine: changes; see studies
Total cholesterol: changes; see studies

Obesity: outcomes studied for Betaine
Grade	Outcome	Effect	Size	Studies	People
	Blood glucose No effect		NoneNo effect		42 people
	Homocysteine	Changes; see studies		4 studies	42 people
Studies that measured homocysteine Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjectsAm J Clin Nutr · PMID 12399266 Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humansJ Nutr · PMID 16365055 Betaine supplementation and plasma homocysteine in healthy volunteersArch Intern Med · PMID 10979070 Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in malesNutr Metab Cardiovasc Dis · PMID 19346114
	Total cholesterol	Changes; see studies		1 study	42 people
Studies that measured total cholesterol Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humansPLoS Med · PMID 15916468
	Blood Pressure
	Body Fat
	High-density lipoprotein (HDL)
	Kidney Function	Improves (the measure goes up)			42 people
	Liver Enzymes	Changes; see studies			42 people
	Low-density lipoprotein (LDL)	Changes; see studies			42 people
	Metabolic Rate	Improves (the measure goes up)			42 people
	Serum Folate	Improves (the measure goes up)			42 people
	Thyroid-Stimulating Hormone	Improves (the measure goes up)			42 people
	Triglycerides	Changes; see studies			42 people
	Weight

Cycling Performance

Anaerobic Capacity
Power Output
Body Fat

Cycling Performance: outcomes studied for Betaine
Outcome	Size	Studies	People
Anaerobic Capacity No effect	NoneNo effect		16 people
Power Output Mixed effect		4 studies
Body Fat
Muscle Mass
Weight

Body Composition

Blood glucose
Homocysteine: changes; see studies
Blood Pressure

Body Composition: outcomes studied for Betaine
Outcome	Effect	Size	Studies	People
Blood glucose No effect		NoneNo effect		42 people
Homocysteine	Changes; see studies		4 studies	42 people
Blood Pressure
Body Fat
Kidney Function	Improves (the measure goes up)			42 people
Low-density lipoprotein (LDL)	Changes; see studies			42 people
Metabolic Rate	Improves (the measure goes up)			42 people
Serum Folate	Improves (the measure goes up)			42 people
Thyroid-Stimulating Hormone	Improves (the measure goes up)			42 people
Weight

Warm- or Hot-Weather Exercise Performance

Anaerobic Capacity
Oxygen Uptake: improves
Blood glucose

Warm- or Hot-Weather Exercise Performance: outcomes studied for Betaine
Outcome	Effect	Size	Studies	People
Anaerobic Capacity No effect		NoneNo effect		10 people
Oxygen Uptake	Improves (the measure goes up)		1 study	10 people
Blood glucose
Heart Rate	Changes; see studies			10 people
Hematocrit	Improves (the measure goes up)			10 people
Hydration (Total Body Water)	Improves (the measure goes up)			10 people
Rating of Perceived Exertion	Improves (the measure goes up)			10 people

Muscle Size & Strength

Anaerobic Capacity
Power Output
IGF-1: improves

Muscle Size & Strength: outcomes studied for Betaine
Outcome	Effect	Size	Studies	People
Anaerobic Capacity No effect		NoneNo effect		24 people
Power Output Mixed effect			4 studies
IGF-1	Improves (the measure goes up)		1 study	12 people
Muscular Endurance No effect			1 study
Weight No effect			1 study
Blood Lactate (Exercise)	Changes; see studies			25 people
Body Fat
Cortisol	Changes; see studies			12 people
Fatigue Symptoms	Changes; see studies			35 people
Growth Hormone	Improves (the measure goes up)			12 people
Heart Rate	Changes; see studies			13 people
Insulin	Changes; see studies			12 people
Muscle Creatine Content	Improves (the measure goes up)			34 people
Muscle Mass
Muscle Oxygenation	Improves (the measure goes up)			13 people
Muscle Soreness	Changes; see studies			24 people
Nitric Oxide	Improves (the measure goes up)			13 people
Oxidative Stress Biomarkers	Changes; see studies			13 people
Rating of Perceived Exertion	Improves (the measure goes up)			37 people
Training Volume	Improves (the measure goes up)			13 people

Weight Loss & Maintenance

Blood glucose
Homocysteine: changes; see studies
Blood Pressure

Weight Loss & Maintenance: outcomes studied for Betaine
Outcome	Effect	Size	Studies	People
Blood glucose No effect		NoneNo effect		42 people
Homocysteine	Changes; see studies		4 studies	42 people
Blood Pressure No effect			1 study
Body Fat No effect			1 study
High-density lipoprotein (HDL) No effect			1 study
Total cholesterol	Changes; see studies		1 study	42 people
Weight No effect			1 study
Kidney Function	Improves (the measure goes up)			42 people
Liver Enzymes	Changes; see studies			42 people
Low-density lipoprotein (LDL)	Changes; see studies			42 people
Metabolic Rate	Improves (the measure goes up)			42 people
Serum Folate	Improves (the measure goes up)			42 people
Thyroid-Stimulating Hormone	Improves (the measure goes up)			42 people
Triglycerides	Changes; see studies			42 people

Key findings

SalivationDry MouthImproves (the measure goes up)
Dry Mouth SymptomsDry MouthImproves (the measure goes down)
Liver EnzymesNonalcoholic Steatohepatitis (NASH)Improves (the measure goes down)

Shop the evidence-backed picks

Betaine products we can link to, in the forms the graded studies used where we can match them.

Grade B

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Studies cited

21 studies from PubMed

Long-term effect of betaine on risk factors associated with the metabolic syndrome in healthy subjectsEur J Clin Nutr · PMID 20978525
The effect of low doses of betaine on plasma homocysteine in healthy volunteersBr J Nutr · PMID 15522136
Betaine, a promising new agent for patients with nonalcoholic steatohepatitis: results of a pilot studyAm J Gastroenterol · PMID 11569700
Influence of betaine consumption on strenuous running and sprinting in a hot environmentJ Strength Cond Res · PMID 18438230
Effect of betaine supplementation on cycling sprint performanceJ Int Soc Sports Nutr · PMID 22471891
Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exerciseEur J Appl Physiol · PMID 22976217
Effect of betaine supplementation on power performance and fatigueJ Int Soc Sports Nutr · PMID 19250531
Effect of 15 days of betaine ingestion on concentric and eccentric force outputs during isokinetic exerciseJ Strength Cond Res · PMID 21747291
Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performanceAmino Acids · PMID 21744011
The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained menJ Strength Cond Res · PMID 22080324
Ergogenic effects of betaine supplementation on strength and power performanceJ Int Soc Sports Nutr · PMID 20642826
Betaine supplementation lowers plasma homocysteine in healthy men and womenJ Nutr · PMID 12730412
Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjectsAm J Clin Nutr · PMID 12399266
Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humansJ Nutr · PMID 16365055
Betaine supplementation and plasma homocysteine in healthy volunteersArch Intern Med · PMID 10979070
Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in malesNutr Metab Cardiovasc Dis · PMID 19346114
Betaine for nonalcoholic fatty liver disease: results of a randomized placebo-controlled trialHepatology · PMID 19824078
Evaluation of the clinical efficacy of a betaine-containing mouthwash and an intraoral device for the treatment of dry mouthJ Oral Pathol Med · PMID 21950587
Safety and effectiveness of topical dry mouth products containing olive oil, betaine, and xylitol in reducing xerostomia for polypharmacy-induced dry mouthJ Oral Rehabil · PMID 17824884
Betaine-containing toothpaste relieves subjective symptoms of dry mouthActa Odontol Scand · PMID 9669455
Effects of a betaine-containing toothpaste on subjective symptoms of dry mouth: a randomized clinical trialJ Contemp Dent Pract · PMID 12761586

Evidence by condition

Muscle Size Strength

General Cardiovascular Health

Key findings

Shop the evidence-backed picks

Studies cited

Related supplements

Guides

Protocols that include Betaine