TRADE NAME: L-carnitine
Chemical Name: L(R)-3-carboxy-2-hydroxy-N,N,N-trimethyl-l-propanaminimum) or levocarnitine
Type of Supplement: Weight Loss
WHAT IT IS: L-carnitine is a non-essential amino acid found throughout cells in the body, but especially concentrated in heart, skeletal muscle tissue and sperm. Belonging to the same family as choline, it is synthesized from L-methionine and l-lysine.
HOW IT WORKS: Other nutrients, such as vitamins B6, C and iron support L-carnitine’s function. About 60-75% of L-carnitine from food is absorbed by the small intestine, with the maximum concentration occurring around three hours1. Those with hyperthyroidism rid L-carnitine from the body more quickly. After L-carnitine is absorbed by the small intestine, it must become acylated in the intestinal mucosa to be distributed to various body tissues1. Once it enters cells, it helps transport long chain fatty acids into the mitochondria for energy production.
PRIMARY EFFECTS: L-carnitine is primarily useful in cardio-protective efforts. As a key component essential for driving energy production in the heart, L-carnitine may help manage cardiac ischemia and peripheral vascular disease, lower triglyceride levels, increase HDL (“good”) cholesterol and improve intermittent claudication (pain upon walking due to poor cardiovascular circulation) symptoms through its ability to improve oxidative phosphorylation and pyruvate utilization in muscle tissue. Interestingly, L-carnitine may heighten exercise capacity in those with Congestive Heart Failure, and may help treat symptoms of CHF. It may also help prevent build up of fat in the liver (commonly induced by excess alcohol or carbohydrate intake). Because of its energy production function, L-carnitine may support male infertility by improving sperm activity. Other energy-related conditions, such as Chronic Fatigue Syndrome, thyroid disorders and weakness from eating disorders may be supported with L-carnitine supplementation.
EFFECTIVE DOSAGE LEVEL: L-carnitine is poorly absorbed, so higher doses may be required to achieve maximal serum concentrations. Research suggests it is most effective between 500-2,000mg/day.
SUPPLEMENT CONFLICTS: Those on prescription medication may want to check with an allied health professional before using high doses of L-carnitine. Vitamin C deficiency may induce L-carnitine deficiency, whereas choline supplementation helps retain L-carnitine in the body.
SIDE EFFECTS: High doses (over 5,000 mg per day) may cause gastrointestinal upset, rash, increased appetite and body odor.
