Weight Loss: Another Role for L-Carnitine
Weight Loss: Another Role for L-Carnitine
I’ve always felt that L-carnitine is deserving of more attention than it gets. Carnitine is a substance that plays an important role in energy production. That alone should get your interest. Even better, it does this by enhancing, or facilitating, the transport of fatty acids across the cell membrane, from the blood stream into the cellular mitochondria, where it is used as “fuel” for energy production. So, not only does it clear fats (fatty acids), but it also boosts energy. In addition, it has been shown to exert antioxidant activity, enhance immune function and support the body’s detox functions.
We have written about carnitine many times in the past, and have discussed it on The Willner Window radio show. You can read these informative articles and transcripts, and listen to audio files if you wish, on the Willner Chemists web site. Go to www.willner.com. Click on “Advanced Search” in the “Library Quick Search” box on the left side of the home page. Select “carnitine” from the drop-down keyword menu.
Why am I bringing it up again? I’ve always felt that L-carnitine should be of value in weight loss. A new, small study was released recently that supports this idea. In the study, they worked with 24 overweight Japanese men. It was a double-blind randomized placebo-controlled study.
The 24 overweight adult men were split into 4 groups: Group A received 500mg L-carnitine; group B received the same with motivation training; group C received placebo and group D placebo plus motivation training.
“Motivation training included a face-to-face 30 minute session with the principal investigator at the baseline visit, where the subjects were informed about L-carnitine and its metabolic functions,” the researchers wrote.
“Furthermore, subjects learned about the beneficial effect of weight loss on the risk of metabolic diseases. Subjects were encouraged to perform daily physical activities like ‘taking stairs’ instead of ‘using escalators’.”
They were also instructed to try to reduce calorie intake to 1500-1800 kcal by taking lighter meals.
Surprisingly, that small 500 mg dose of L-carnitine seemed to make a difference. Only group B–the group receiving carnitine and motivational training--showed a statistically significant weight reduction of 1.1kg compared to an increase of 0.7kg in the placebo non-motivated group.
Now this was a small study, and certainly should considered limited in value. But it’s one of those situations where we are dealing with a substance, a supplement in this case, that has many beneficial actions. In this case, the researches also measured a decrease in triglyceride levels, for example. Even though it was a small study, and only for four weeks, the researchers point out that the results were significant.
“This may be a crucial limitation that weakens the significance of the results, although ... Low dosage L-carnitine combined with motivation may have a beneficial effect on several metabolic syndrome risk parameters, including triglycerides and adiponectin, which could offer a safe, low cost, and easily applicable strategy targeting weight loss in overweight humans."
(Food and Nutrition Sciences, Published Online February 2013. ‘A Pilot Clinical Trial on L-Carnitine Supplementation in Combination with Motivation Training: Effects on Weight Management in Healthy Volunteers.’ Authors: Satoshi Odo, Koji Tanabe, Masamitsu Yamauchi)
Carnitine may be useful for preventing and/or treating many conditions. A list is presented in Dr. Alan Gaby’s book, Nutritional Medicine (see table).
“Although carnitine is synthesized by the body, there are a number of circumstances in which the amount synthesized is inadequate to meet physiological requirements. Primary carnitine deficiency is a rare condition that results from inborn errors of metabolism . . . Secondary carnitine deficiency is more common, and may occur in association with various diseases and clinical situations, including burns, infection, surgery, starvation, consumption of a ketogenic diet, malabsorption, use of certain medications, renal tubular disorders, dialysis treatment, liver dysfunction, and infancy (particularly with prematurity). Secondary carnitine deficiency usually results from increased urinary carnitine excretion, decreased synthesis, or a combination of these factors . . .”
Manifestations of secondary carnitine deficiency may include fatigue; muscle weakness; lipid accumulation in skeletal muscle, myocardium, and liver; and hypoglycemia. . .”
(Gaby, Alan R., MD. Nutritional Medicine. Alan R. Gaby, M.D., 01/2011.)
There are several different forms of carnitine available in supplement form. We have explained the differences in many of the references you will find in the reference library section of the willner.com web site. Here is what Dr. Gaby has to say:
“L-Carnitine is available over the counter . . . Propionyl-L-carnitine is a carnitine derivative that has been used in some studies as an alternative to L-carnitine. Propionyl-L-carnitine has been reported to have greater affinity than L-carnitine for cardiac and skeletal muscle. Acetyl-L-carnitine . . . is another carnitine derivative that functions as a cholinergic neurotransmitter and can also serve as a source of L-carnitine. The clinical indications for L-carnitine and acetyl-L-carnitine differ, and these compounds are not used interchangeably.
Dosage and administration: The most frequently used dosages of L-carnitine for adults in clinical trials have been 1–2 g/day, although lower and higher dosages have been used in some studies. . . Taking L-carnitine in divided doses, as opposed to once a day, may increase the total amount absorbed, particularly at the higher end of the dosage range.”