What is L-Carnitine and what does it do?

L-Carnitine is an amino acid derivative that helps transport long-chain fatty acids into mitochondria to be used for energy. The body can make it, and it is also obtained from foods, especially animal products.

Does L-Carnitine help with weight loss or fat burning?

It may modestly support fat oxidation and body composition, with effects varying by person. Benefits are more likely when combined with diet and exercise rather than used alone.

How much L-Carnitine should I take?

Common supplemental amounts are about 500–2,000 mg per day. Dosing can depend on the product form and individual goals, so follow label directions and clinician advice if you have medical conditions.

Can L-Carnitine improve exercise performance and recovery?

Some people report improved endurance and reduced fatigue or muscle soreness, particularly with consistent use. Results are mixed and may depend on training status and activity type.

What are the side effects or precautions with L-Carnitine?

Possible side effects include gastrointestinal upset and, in some cases, a fishy body odor. People with medical conditions or those taking medications should consult a healthcare professional before use.

313 wetenschappelijk onderbouwde voedingsstoffen

3251 bronnen geraadpleegd

Informatie ingedeeld naar bewijs

Verken op doel of categorie

Voedingsstof vinden

Populaire keuzes

Eicosapentaenoic acid (EPA)Vitamin D3 Docosahexaenoic acid (DHA)Zinc (Bisglycinate)

313 voedingsstoffen totaal

Vitamin B

Vitamin B1 (Thiamine)

Vitamin B2 (Riboflavin)

Vitamin B3 (Niacin)

Vitamin B5 (Pantothenic Acid)

Vitamin B6 (Pyridoxine)

Vitamin B7 (Biotin)

Vitamin B9 (Folic Acid)

Vitamin B12 (Methylcobalamin)

Vitamin B12 (Cobalamin)

Vitamin A & Carotenoids

Vitamin C

Vitamin D

Vitamin E

Vitamin K

Vitaminoids

Trimethylglycine (Betaine)

NMN (Nicotinamide Mononucleotide)

Pyrroloquinoline Quinone (PQQ)

D-Chiro-Inositol

Coenzym Q10 (Ubiquinone)

Betaine HCL

Nicotinamide Riboside

Vitamin B8 (Myo-Inositol)

Choline

Citicoline (CDP-Choline)

Coenzyme Q10 (Ubiquinol)

Calcium

Calcium Alpha-Ketoglutarate

Magnesium

Magnesium Bisglycinate

Magnesium L-Threonate

Trace Minerals

Copper (Bisglycinate)

Chromium Picolinate

Manganese (Bisglycinate)

Zinc

Pentadecanoic Acid (C15:0)

Phosphatidylserine

R-Alpha Lipoic Acid

Black Cumin Oil

Extra Virgin Olive Oil

Ceratiq wheat oil extract

Phospholipids

Algae Oil

Fish Oil

Conjugated Linoleic Acid

Gamma-Aminobutyric Acid

Alpha-Linolenic Acid

Gamma-Linolenic Acid

Omega-3

Docosapentaenoic acid (DPA)

Eicosapentaenoic acid (EPA)

Docosahexaenoic acid (DHA)

AminoMar

Acetyl-L-Carnitine

PABA (para-aminobenzoic acid)

Essential Amino Acids

Conditionally Essential Amino Acids

L-Theanine

Non-Essential Amino Acids

Beta-Alanine

L-Cysteine Hydrochloride

Amino Acid Derivative

Taurine

Creatine (Hydrochloride)

L-Arginine Alpha-Ketoglutarate

Creatine (Monohydrate)

Akkermansia muciniphila

Lactobacillus Reuteri

Probiotics

Bifidobacterium longum BB536

Prebiotics

Stinging Nettle Extract

Pomegranate Polyphenols

Red Beet Extract

Pine Extract (Pycnogenol)

Oligomeric Proanthocyanidins (OPC)

Ashwagandha Root Extract

Methylsulfonylmethane (MSM)

Citrus Sinensis Extract

Horsetail Stem Extract

Flax Seed Extract

Sulforaphane Glucosinolate

Garlic Extract

Black Pepper

Apricot Kernel Extract

Lovage

Spiny Rest Harrow Root Extract

Juniper Berry Extract

Bearberry Leaf Extract

White Kidney Bean Extract

Lady’s Mantle Extract

Bitter Orange Extract

St. John’s Wort Extract

Japanese Knotweed Extract

Hydroxytyrosol/tyrosol

Olive extract

Sesame seed lignan extract

Broccoli Sprout Extract

Cranberry Extract

Flavon Glycosides

Gentian Root Extract

Griffonia simplicifolia Extract

Ajuga Turkestanica Extract

Amaranthus Leaf Extract

Banaba Extract

Boswellia Extract

Capsaicin

Cayenne Pepper Extract

Celery Extract

Ceylon Cinnamon Extract

Chamomile Extract

Charantin

Chinese Goldthread Root Extract

Citrus Aurantium Extract

Cocoa Extract

Cyanotis Arachnoidea Extract

Fadogia Agrestis Extract

Garcinia Cambogia Extract

Goldenrod Extract

Green Tea Extract

Guarana Extract

Horse Chestnut Extract

Grapefruit Seed Extract

Grape Vine Leaf Extract

Green Tea Polyphenols

Epigallocatechin Gallate (EGCG)

Adaptogens

Cordyceps sinensis extract

Ginsenoside

Lion's Mane (Hericium erinaceus)

Ginseng Extract

Cat's Claw (Uncaria tomentosa)

Arjuna (Terminalia arjuna)

Tribulus Terrestris Extract

Rhodiola rosea

Panax Ginseng Extract

Mushrooms

Reishi Extract

Astragalus Polysaccharides

Hyaluronic Acid

Glucosamine Sulfate

Chondroitin Sulfate

Glucosamine Sulphate 2KCL

L-Carnitine

Moderate study situation·7/10

A higher score indicates better study conditions, but not necessarily effectiveness.

L-Carnitine is an amino acid derivative involved in energy metabolism and studied for support in fat loss, exercise performance, and heart health.

Exercise Recovery Cardiovascular Support Exercise Performance Cholesterol Management Weight Management

dose range

500–2000 mg

Divide into 1–3 doses per day.

Consumption

Take with meals or a carbohydrate source to improve absorption.

Not fat-soluble.

Best time

Morning, pre- or post-workout timing may be optimal, especially for exercise support.

Description

L-Carnitine is a nutrient and dietary supplement that enables the transport of fatty acids into mitochondria for energy production. It is found in animal products and is also synthesized in the body. Interest in L-carnitine is due to its potential to support energy, physical performance, and cardiovascular health, although its absorption from supplements is limited.

benefits

Main effects with level of evidence

Moderate

Note on evidence

There is moderate evidence supporting L-carnitine's benefit for exercise performance, recovery, and some cardiovascular conditions. Effects on weight loss are modest and not universal.

May Support Fat Metabolism and Body Composition

Moderate

Supplementing with L-carnitine modestly enhances fat oxidation and may support weight loss, particularly in overweight or older adults.

Particularly relevant for: Adults with overweight · Older adults · Individuals seeking weight management

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet 2 · Effect of L-carnitine supplementation on weight loss in adults: a systematic review and meta-analysis of randomized controlled trials

May Improve Exercise Performance and Recovery

Moderate

L-carnitine supplementation can improve endurance, reduce perceived fatigue, and lessen muscle soreness, with most benefit seen in endurance activities or in physically active people.

Particularly relevant for: Athletes · Physically active adults · Exercise enthusiasts

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet 3 · Effectiveness of L-carnitine supplementation for muscle soreness and recovery: A systematic review and meta-analysis of randomized controlled trials 6 · Examine.com: L-carnitine

Cardiovascular Support in Certain Conditions

Moderate

L-carnitine has been shown to improve exercise tolerance and symptoms in some people with chronic heart disease, angina, or heart failure as an adjunct to medical care.

Particularly relevant for: Adults with heart disease · Adults with angina · Those under cardiac care

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet 4 · L-carnitine in the treatment of chronic heart disease: a meta-analysis of randomized controlled trials

Safety & Information

Important safety information & known risks

For educational purposes only • not medical advice

Generally well-tolerated at typical doses, but special risk exists in certain conditions.

warning notices

Mild side effects (nausea, diarrhea, stomach upset) can occur, particularly at higher doses.
Rare reports of increased seizure risk, primarily in those with pre-existing epilepsy.
Possible interaction with thyroid medications and certain anticonvulsants.
Avoid use if you have hypothyroidism, unless directed by a physician.
Avoid use if you have a history of seizures, as L-carnitine may increase seizure risk.
Use only with a healthcare provider's supervision if you are pregnant or breastfeeding.
Monitor for drug interactions if you are taking thyroid hormone replacement medication.

Known interactions with medications

Thyroid medications
Anticonvulsants

Contraindications / special precautions

Hypothyroidism unless directed by a clinician
Seizure disorders unless under medical supervision

interactions

Important interactions between active ingredient ↔ supplement / medication / food

L-carnitine has notable interactions with thyroid medications, some anticonvulsants, and can interact with certain nutrients and drugs affecting seizure threshold.

L-carnitine may reduce uptake or activity of thyroid hormones.

drug · Thyroid hormone medication

MonitorModerate

Why

It can interfere with thyroid hormone entry into cells, potentially reducing their effectiveness.

recommendation

Monitor thyroid status; consult your physician if taking thyroid medications.

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet

May lower seizure threshold in some with history of seizures.

drug · Anticonvulsant medication

CautionModerate

Why

L-carnitine supplementation has been associated with rare seizure events in susceptible individuals.

recommendation

Avoid use unless under strict medical supervision if you have a history of seizures.

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet 5 · EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the safety of L-carnitine tartrate, L-carnitine fumarate, and L-carnitine propionyl as sources for L-carnitine added for nutritional purposes to food supplements and foods for particular nutritional uses

mechanisms of action

Brief explanations of how it works

Fatty Acid Transport into Mitochondria

L-carnitine facilitates the import of long-chain fatty acids into mitochondria, enabling their oxidation for energy production, especially during periods of increased energy demand.

1 · NIH Office of Dietary Supplements: Carnitine Fact Sheet 6 · Examine.com: L-carnitine

Modulation of Exercise Recovery

L-carnitine helps reduce markers of muscle damage and soreness following exercise, potentially by lowering oxidative stress and increasing cellular repair.

3 · Effectiveness of L-carnitine supplementation for muscle soreness and recovery: A systematic review and meta-analysis of randomized controlled trials 6 · Examine.com: L-carnitine