Introduction

L-Carnitine is a conditionally essential amino acid–like compound that plays a crucial role in energy metabolism by transporting fatty acids into the mitochondria, where they are burned for energy. It is especially important for heart health, muscle performance, brain function, and fat metabolism.

What Is L-Carnitine?

L-Carnitine is synthesized in the body from lysine and methionine, but dietary intake is also important.

• Type: Conditionally essential amino acid–like compound
• Main role: Fat transport and energy production
• Storage: Muscles, heart, brain

How L-Carnitine Works in the Body

L-Carnitine enables the transport of long-chain fatty acids into mitochondria for oxidation.

• Transports fatty acids into mitochondria
• Supports cellular energy (ATP) production
• Helps reduce buildup of toxic fatty acid byproducts
• Supports heart and muscle function

Sources of L-Carnitine

• Red meat (highest source)
• Poultry
• Fish
• Dairy products
• Small amounts in plant foods

L-Carnitine Deficiency

L-Carnitine deficiency may occur due to genetic disorders, liver or kidney disease, or inadequate intake.

Possible deficiency-related symptoms include:

• Chronic fatigue
• Muscle weakness
• Poor exercise tolerance
• Heart function impairment
• Brain fog

Dosage & How to Take L-Carnitine

• General support: 500–1000 mg/day
• Fat metabolism & energy: 1000–2000 mg/day
• Athletes: 1500–3000 mg/day

L-Carnitine is often taken with meals or before exercise.

Forms of L-Carnitine

• L-Carnitine (base form)
• Acetyl-L-Carnitine (ALCAR)
• Propionyl-L-Carnitine
• L-Carnitine tartrate

Benefits & Uses

• Enhances fat burning and energy production
• Supports heart and cardiovascular health
• Improves exercise performance and recovery
• Supports brain function and mental clarity
• May support male fertility and sperm health

Safety, Side Effects & Precautions

• Generally safe at recommended doses
• High doses may cause nausea or fishy body odor
• People with kidney disease should consult a doctor
• Use cautiously in seizure disorders

Special Populations

• Athletes: Supports endurance and recovery
• Older adults: Supports energy and brain health
• People with heart conditions: Supports cardiac energy metabolism
• Vegetarians: May have lower dietary intake

Frequently Asked Questions

What does L-Carnitine do in the body?

L-Carnitine transports fatty acids into mitochondria for energy production.

Is L-Carnitine good for weight loss?

It supports fat metabolism but works best with diet and exercise.

Can L-Carnitine be taken daily?

Yes. Daily supplementation is safe for healthy individuals.

Which form of L-Carnitine is best?

ALCAR for brain health, L-Carnitine tartrate for exercise performance.

Best time to take L-Carnitine?

With meals or 30–60 minutes before workouts.