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L-carnitine has been shown to support the heart and cardiovascular system, help athletes optimize their performance, help burn fat more easily, help rejuvenate our aging brains and even promote healthy sperm function.

L-carnitine is critical for energy production in every cell of your body. It carries fat, in the form of fatty acids, to the mitochondrial inner membrane where energy is produced. Without L-carnitine, the normal burning of fat cannot take place.

In the brain and nervous tissues, acetyl L-carnitine is important in energy production, but is more importantly a precursor to acetylcholine. This powerful neurotransmitter plays a vital role in maintaining healthy brain function, memory and mood as we age.

Health benefits of L-carnitine

Cardiovascular
Congestive heart failure, irregular heart rhythms and peripheral vascular disease (poor circulation to the arms or legs) are all common consequences of cardiovascular disease. L-carnitine has been shown to support the cardiovascular system, even in the face of these consequences. 70% of the metabolic energy required by the heart is supplied by fatty acids. No other organ in the body has higher concentrations of L-carnitine.

Sports and muscle metabolism
During strenuous physical exercise, the body requires large amounts of glucose and fatty acids to produce energy. L-carnitine has been shown to reduce the respiratory quotient (RQ) in athletes. A lower RQ reflects more fatty acid burning and less glucose utilization. This glucose-sparing effect helps delay the onset of exhaustion and enhances performance. Improved performance has been confirmed by the improved VO2 Max (a measure of maximal aerobic capacity) of athletes using L-carnitine.

Dr. William Kraemer, from the Ball State Human Performance Laboratory, presented the results of a study on muscle soreness in "weekend warrior" athletes. It showed that L-carnitine tartrate, prior to high intensity exercise, is effective in assisting muscle recovery and reducing muscle soreness following exercise.

Fat metabolism and weight loss
Because of its vital role in fat metabolism, another obvious benefit of L-carnitine supplementation is in weight loss. Numerous animal and human studies have shown L-carnitine to promote muscle deposition instead of fat.

Brain health
Because of its unique chemical properties, acetyl L-carnitine (ALC) is able to cross into the brain easily, providing neuroprotective benefits. Besides aiding in fat metabolism, ALC directly stimulates the production of acetylcholine, a powerful neurotransmitter. Many current studies of L-carnitine and age-related changes in memory or mood have shown L-carnitine to benefit or delay those changes.

Sperm motility
Infertility research has shown approximately 30% of cases to be directly related to the man alone, and not the woman. One Italian study showed that 78% of men had improvement in sperm counts and motility with 3 grams of L-carnitine daily.

The best form of L-carnitine
L-carnitine can be found in many forms, including acetyl L-carnitine, L-carnitine tartrate, L-carnitine fumarate, and the most common form, L-carnitine base. The base form is ideal for liquid supplements, but in capsules or tablets, it can soak up water from the air and turn bad. Some large chemical companies have developed more stable forms that are ideal for capsules or tablets called L-carnitine tartrate and fumarate. The only form that can cross the blood-brain barrier is acetyl L-carnitine. It has found its unique use in "brain products."

How much do I need to take?
Most people who do not see results with L-carnitine supplements are probably not taking enough. Most of the scientific literature describes effective doses from 1 to 4 grams of L-carnitine. For brain/mood benefits, studies suggest taking 1 to 3 grams of acetyl L-carnitine daily.