Table of ContentsView AllTable of ContentsWeight LossUsesDosageTypesSide EffectsWho Can BenefitFood Sources
Table of ContentsView All
View All
Table of Contents
Weight Loss
Uses
Dosage
Types
Side Effects
Who Can Benefit
Food Sources
L-carnitine—also known aslevocarnitine—is an amino acid that occurs naturally in the body and is available as a supplement. Some studies report weight loss results of 2 to 3 pounds with L-carnitine, but these results are mixed and more research is needed.In some cases, weightgainis actually the goal of using L-carnitinesupplements.
L-carnitine aids in metabolism and can be used to supplement your body’s natural carnitine to produce energy and remove toxins from cells. Because of this action, L-carnitine is sometimes taken to improve physical performance, or used when treating conditions such as end-stage kidney failure.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
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Does L-Carnitine Aid Weight Loss?
L-carnitine moves fatty acids into the cells to produce energy, so it has been assumed that it can help with weight loss. Some studies report L-carnitine weight loss results that support this theory but more research is needed for conclusions to be drawn.
L-Carnitine and ObesityPeople diagnosed with obesity or overweight may improve their weight, waist circumference, and fat mass when treatment includes L-carnitine. There was less evidence of improved body fat percentage, according to a 2020 analysis of L-carnitine research studies.
L-Carnitine and Obesity
People diagnosed with obesity or overweight may improve their weight, waist circumference, and fat mass when treatment includes L-carnitine. There was less evidence of improved body fat percentage, according to a 2020 analysis of L-carnitine research studies.
Other Studied Uses
L-carnitine is a crucial component of energy production in the body. L-carnitine also helps to move toxins out of the cells.It may help with various symptoms of different diseases and conditions, as outlined below.
Alzheimer’s Disease
Researchers have studied L-carnitine to determine if it can help produce acetylcholine.
A 2020 review of several articles regarding the use of L-carnitine for dementia and Alzheimer’s disease found mixed results.Many of the studies reviewed showed favorable outcomes with L-carnitine use, whereas other studies showed minimal to no results.
Further research is needed on the effects of L-carnitine on people with Alzheimer’s disease.
Heart Disease
A study from 2017 found benefits from L-carnitine supplementation in people with chronicheart failure. Improvements in several areas of heart function included cardiac output and left ventricular ejection fraction.
Other studies have found that L-carnitine supplementation caused negative effects on the cardiovascular system in people diagnosed with an underlying metabolic disorder or predisposed to cardiovascular risk.Research still needs to be conducted to determine if L-carnitine supplementation is an effective treatment for cardiovascular disease.
Kidney Disease
People receiving peritoneal dialysis treatment for renal (kidney) failure often demonstrate L-carnitine deficiency. This deficiency is associated with symptoms that include:
Supplemental L-carnitine is not recommended in all cases, but some people may benefit when L-carnitine is added to the fluid used for dialysis. More study is needed to understand this use.
Athletic Performance
Carnitine preserves fuel for the muscles and promotes the breakdown of fats into energy.As a result, some people take L-carnitine supplements to improve their athletic performance.
However, research has shown no proof that L-carnitine supplements improve physicalexerciseperformance.
Fertility
L-carnitine has been used successfully to improve fertility. Research showed that supplementation improved sperm motility.
Other research has shown that L-carnitine supplementation improvedovulationand pregnancy rates in those withpolycystic ovary syndrome(PCOS). People with PCOS who took the supplement had 64.4% higher ovulation rates. It also improved pregnancy rates and lessened miscarriages in those with PCOS.
Daily Dosage
Carnitine is made in the liver, kidney, and brain. The body stores 95% of carnitine in the heart and skeletalmuscles. The body needs 15 milligrams (mg) per day of carnitine from either outside sources—like food—or from the body which makes its own carnitine.
Most people who eat a diet consisting of both meat and nonmeat sources will consume between 24 and 145 mg of carnitine each day. However,people who follow a vegan dietwill likely consume only 1.2 mg per day.
Oddly, diet does not seem to influence how much carnitine the body makes. According to the National Institutes of Health, a person who eats a vegan diet still produces 14.4 mg of carnitine per day.
Since carnitine is not considered an essential nutrient, there are no recommended daily amounts for supplements.
Types of L-Carnitine Supplements
L-carnitine is a type of carnitine. There are several forms of carnitine available for supplementation. They include:
Carnitine is typically taken as an oral supplement but can be given through an intravenous (IV) line.
Side Effects and Safety
There are potential side effects when too much L-carnitine is taken. They include:
Always talk to a healthcare provider before starting a carnitine supplement.
Who Can Benefit from Supplements?
L-carnitine supplements may offer benefits to specific users, including:
People who lose muscle due to cancer diagnosis and treatment (calledcachexia) may benefit from L-carnitine supplements, too, but research results haven’t shown a strong benefit and more study is needed.Always talk to a healthcare provider before starting a carnitine supplement.
The best source of L-carnitine is in food. The body’s ability to absorb L-carnitine in food is much higher than in a supplement. The best sources (listed from greatest source to lowest) of L-carnitine include:
Summary
L-carnitine is anamino acidthat is produced in the body and is found in many animal-based food products. It produces energy and removes toxins from the cells. L-carnitine is often advertised as a supplement to help weight loss, improve physical performance, and more.
Research still needs to be done to confirm the effectiveness of L-carnitine supplementation. Always talk to a healthcare provider before starting a supplement as it may adversely interact with other medications or affect certain conditions.
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health.Carnitine.Alam J, Fahim SM, Islam MR, Alam MA, Gazi MA, Ahmed T.Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial.J Nutr. 2024 Mar;154(3):949-961. doi:10.1016/j.tjnut.2024.01.031Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A.Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.Clinical Nutrition ESPEN. 2020;37:9-23. doi:10.1016/j.clnesp.2020.03.008Askarpour M, Hadi A, Miraghajani M, Symonds ME, Sheikhi A, Ghaedi E.Beneficial effects of l-carnitine supplementation for weight management in overweight and obese adults: An updated systematic review and dose-response meta-analysis of randomized controlled trials.Pharmacol Res. 2020 Jan;151:104554. doi:10.1016/j.phrs.2019.104554Centers of Disease Control and Prevention.Alzheimer’s disease and related dementias.Pennisi M, Lanza G, Cantone M, et al.Acetyl-l-carnitine in dementia and other cognitive disorders: a critical update.Nutrients. 2020;12(5):1389. doi:10.3390/nu12051389Song X, Qu H, Yang Z, Rong J, Cai W, Zhou H.Efficacy and safety of l-carnitine treatment for chronic heart failure: a meta-analysis of randomized controlled trials.BioMed Research International. 2017;2017:1-11. doi:10.1155/2017/6274854Bonomini M, Di Liberato L, Zammit V, Arduini A.Current Opinion on Usage of L-Carnitine in End-Stage Renal Disease Patients on Peritoneal Dialysis.Molecules.2019 Sep 23;24(19):3449. doi:10.3390/molecules24193449Gnoni A, Longo S, Gnoni GV, Giudetti AM.Carnitine in human muscle bioenergetics: can carnitine supplementation improve physical exercise?Molecules. 2020;25(1):182. doi:10.3390/molecules25010182Mount Sinai.Carnitine (l-carnitine).Alhasaniah AH.l-carnitine: Nutrition, pathology, and health benefits.Saudi J Biol Sci. 2023 Feb;30(2):103555. doi:10.1016/j.sjbs.2022Braha A, Albai A, Timar B, Negru Ș, Sorin S, Roman D,et al.Nutritional Interventions to Improve Cachexia Outcomes in Cancer-A Systematic Review.Medicina (Kaunas). 2022 Jul 21;58(7):966. doi:10.3390/medicina58070966
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health.Carnitine.Alam J, Fahim SM, Islam MR, Alam MA, Gazi MA, Ahmed T.Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial.J Nutr. 2024 Mar;154(3):949-961. doi:10.1016/j.tjnut.2024.01.031Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A.Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.Clinical Nutrition ESPEN. 2020;37:9-23. doi:10.1016/j.clnesp.2020.03.008Askarpour M, Hadi A, Miraghajani M, Symonds ME, Sheikhi A, Ghaedi E.Beneficial effects of l-carnitine supplementation for weight management in overweight and obese adults: An updated systematic review and dose-response meta-analysis of randomized controlled trials.Pharmacol Res. 2020 Jan;151:104554. doi:10.1016/j.phrs.2019.104554Centers of Disease Control and Prevention.Alzheimer’s disease and related dementias.Pennisi M, Lanza G, Cantone M, et al.Acetyl-l-carnitine in dementia and other cognitive disorders: a critical update.Nutrients. 2020;12(5):1389. doi:10.3390/nu12051389Song X, Qu H, Yang Z, Rong J, Cai W, Zhou H.Efficacy and safety of l-carnitine treatment for chronic heart failure: a meta-analysis of randomized controlled trials.BioMed Research International. 2017;2017:1-11. doi:10.1155/2017/6274854Bonomini M, Di Liberato L, Zammit V, Arduini A.Current Opinion on Usage of L-Carnitine in End-Stage Renal Disease Patients on Peritoneal Dialysis.Molecules.2019 Sep 23;24(19):3449. doi:10.3390/molecules24193449Gnoni A, Longo S, Gnoni GV, Giudetti AM.Carnitine in human muscle bioenergetics: can carnitine supplementation improve physical exercise?Molecules. 2020;25(1):182. doi:10.3390/molecules25010182Mount Sinai.Carnitine (l-carnitine).Alhasaniah AH.l-carnitine: Nutrition, pathology, and health benefits.Saudi J Biol Sci. 2023 Feb;30(2):103555. doi:10.1016/j.sjbs.2022Braha A, Albai A, Timar B, Negru Ș, Sorin S, Roman D,et al.Nutritional Interventions to Improve Cachexia Outcomes in Cancer-A Systematic Review.Medicina (Kaunas). 2022 Jul 21;58(7):966. doi:10.3390/medicina58070966
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Institutes of Health.Carnitine.Alam J, Fahim SM, Islam MR, Alam MA, Gazi MA, Ahmed T.Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial.J Nutr. 2024 Mar;154(3):949-961. doi:10.1016/j.tjnut.2024.01.031Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A.Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.Clinical Nutrition ESPEN. 2020;37:9-23. doi:10.1016/j.clnesp.2020.03.008Askarpour M, Hadi A, Miraghajani M, Symonds ME, Sheikhi A, Ghaedi E.Beneficial effects of l-carnitine supplementation for weight management in overweight and obese adults: An updated systematic review and dose-response meta-analysis of randomized controlled trials.Pharmacol Res. 2020 Jan;151:104554. doi:10.1016/j.phrs.2019.104554Centers of Disease Control and Prevention.Alzheimer’s disease and related dementias.Pennisi M, Lanza G, Cantone M, et al.Acetyl-l-carnitine in dementia and other cognitive disorders: a critical update.Nutrients. 2020;12(5):1389. doi:10.3390/nu12051389Song X, Qu H, Yang Z, Rong J, Cai W, Zhou H.Efficacy and safety of l-carnitine treatment for chronic heart failure: a meta-analysis of randomized controlled trials.BioMed Research International. 2017;2017:1-11. doi:10.1155/2017/6274854Bonomini M, Di Liberato L, Zammit V, Arduini A.Current Opinion on Usage of L-Carnitine in End-Stage Renal Disease Patients on Peritoneal Dialysis.Molecules.2019 Sep 23;24(19):3449. doi:10.3390/molecules24193449Gnoni A, Longo S, Gnoni GV, Giudetti AM.Carnitine in human muscle bioenergetics: can carnitine supplementation improve physical exercise?Molecules. 2020;25(1):182. doi:10.3390/molecules25010182Mount Sinai.Carnitine (l-carnitine).Alhasaniah AH.l-carnitine: Nutrition, pathology, and health benefits.Saudi J Biol Sci. 2023 Feb;30(2):103555. doi:10.1016/j.sjbs.2022Braha A, Albai A, Timar B, Negru Ș, Sorin S, Roman D,et al.Nutritional Interventions to Improve Cachexia Outcomes in Cancer-A Systematic Review.Medicina (Kaunas). 2022 Jul 21;58(7):966. doi:10.3390/medicina58070966
National Institutes of Health.Carnitine.
Alam J, Fahim SM, Islam MR, Alam MA, Gazi MA, Ahmed T.Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial.J Nutr. 2024 Mar;154(3):949-961. doi:10.1016/j.tjnut.2024.01.031
Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A.Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.Clinical Nutrition ESPEN. 2020;37:9-23. doi:10.1016/j.clnesp.2020.03.008
Askarpour M, Hadi A, Miraghajani M, Symonds ME, Sheikhi A, Ghaedi E.Beneficial effects of l-carnitine supplementation for weight management in overweight and obese adults: An updated systematic review and dose-response meta-analysis of randomized controlled trials.Pharmacol Res. 2020 Jan;151:104554. doi:10.1016/j.phrs.2019.104554
Centers of Disease Control and Prevention.Alzheimer’s disease and related dementias.
Pennisi M, Lanza G, Cantone M, et al.Acetyl-l-carnitine in dementia and other cognitive disorders: a critical update.Nutrients. 2020;12(5):1389. doi:10.3390/nu12051389
Song X, Qu H, Yang Z, Rong J, Cai W, Zhou H.Efficacy and safety of l-carnitine treatment for chronic heart failure: a meta-analysis of randomized controlled trials.BioMed Research International. 2017;2017:1-11. doi:10.1155/2017/6274854
Bonomini M, Di Liberato L, Zammit V, Arduini A.Current Opinion on Usage of L-Carnitine in End-Stage Renal Disease Patients on Peritoneal Dialysis.Molecules.2019 Sep 23;24(19):3449. doi:10.3390/molecules24193449
Gnoni A, Longo S, Gnoni GV, Giudetti AM.Carnitine in human muscle bioenergetics: can carnitine supplementation improve physical exercise?Molecules. 2020;25(1):182. doi:10.3390/molecules25010182
Mount Sinai.Carnitine (l-carnitine).
Alhasaniah AH.l-carnitine: Nutrition, pathology, and health benefits.Saudi J Biol Sci. 2023 Feb;30(2):103555. doi:10.1016/j.sjbs.2022
Braha A, Albai A, Timar B, Negru Ș, Sorin S, Roman D,et al.Nutritional Interventions to Improve Cachexia Outcomes in Cancer-A Systematic Review.Medicina (Kaunas). 2022 Jul 21;58(7):966. doi:10.3390/medicina58070966
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