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L-Carnitine and Fat Loss

L-Carnitine and Fat Loss

L-Carnitine is a naturally occurring amino acid that helps your body turn fat into energy.  L-carnitine is used not only for fat metabolism, but also heart health, brain function, and muscular function.   The main function in the body however, is to transport fatty acids into the mitochondria of cells to help energy production and release stored body fat (triglycerides).

L-Carnitine was first discovered in 1905 and was found to be a derivative of the amino acids Lysine and Methionine.  It was not until the 1960’s that we understood how L-Carnitine functioned in the body and discovered that it was produced from essential amino acids.   Physiologically, approximately 80% of the amino acids that we need to survive are synthesized by our bodies, and the remaining 20% are referred to as the essential amino acids. The term essential means that our body cannot produce these proteins and therefore need an external supply in the form of a supplement.  Since L-carnitine is made from essential amino acids, it is classified as a conditionally essential amino acid.  Essential amino acids (branched chain amino acids) are a healthy addition to any diet or supplement program regardless if you are an athlete or not.

In the presence of essential amino acids, L-carnitine is synthesized primarily in the liver and to a lesser extent in the kidneys.  After it is produced or consumed, it is transported to heart and skeletal muscle tissues in the body that use fatty acids (triglycerides) as a primary fuel source  where it functions to direct fats into the mitochondria in the cells from the blood stream for use in cellular energy production.  L-carnitine, therefore, plays a very important role in energy production through the beta-oxidation of long-chain fatty acids (triglycerides). L-carnitine has other functions as well which include a role in muscle contraction, regulation of protein balance and maintenance of a heart tissue.

L-carnitine works by stimulating your body into burning more triglycerides.  With the supplementation of L-carnitine, your body has a greater affinity of using fatty acids (triglycerides) as an energy source as compared to carbohydrates.  By burning triglycerides, your body can spare its supply of glycogen that is stored in the liver which it can use for other bodily needs.  Research shows that during exercise, your body will burn fat at a rate of 75-80% of its maximum exertion (this is why heart rate monitors are very useful during exercise).  This means that at 75% of your maximum exertion, your body will burn fat before carbohydrates during strenuous exercise.  If less glycogen (from carbohydrates) is burned, more fat is mobilized due to the role of L-carnitine resulting in increased fat loss.  L-carnitine allows the body to burn more fat, save more glycogen, and ultimately boost stamina and endurance due to the metabolic process of using fat as a fuel source. By providing more fat to the muscles, L-carnitine makes accessible an otherwise unavailable energy source. Research studies also show that “oral L-carnitine reduces fat mass, increases muscle mass, and reduces fatigue, which may contribute to weight.”

L-Carnitine has also been proposed as a treatment for many health conditions because it also acts as an antioxidant. Antioxidants fight harmful particles in the body known as free radicals, which damages cells and DNA. Antioxidants can neutralize free radicals and may reduce or help prevent some of the damage they cause.  After L-carnitine stimulates the mobilization of fats and then transports them into the mitochondria in the cell for energy production, any residual carnitine facilitates the removal of the toxic byproducts of cellular metabolism and degeneration that accompany exercise which will reduce muscle fatigue and facilitate a faster recovery period.  It is also being researched in the fields of cardiac conditions, claudication, diabetes, neuropathy, Alzheimer’s and hyperthyroidism.

As with any supplement, some people may have mild side effects towards L-Carnitine.  There may be interactions with medications and you should take them under the supervision of a knowledgeable health care provider due to its conditional classification.  Also, if you have any vascular disease, high blood pressure, liver disease, diabetes, kidney disease or seizures, you should talk to your health care provider prior to taking L-carnitine.  Doses above 5 or more grams per day have been shown to have mild reactions in the body such as diarrhea, increased appetite, body odor, and rash; however, these are not very common.

Recommended doses of L-carnitine vary depending on the athletic regimen (or the health condition being treated). The usual dose is between 1 – 3 g per day.  L-carnitine should be consumed on an empty stomach approximately 30 minutes before breakfast and can also be used as  part of a pre-workout supplement.  Consuming L-carnitine as a pre-workout supplement will also help stimulate fat metabolism at a more efficient rate due to its availability in the bloodstream when exercising in your target heart rate.

In conclusion, L-Carnitine, it is the essential amino acid in your body’s optimum fat burning process. Your body can only make so much of L-carnitine and even with the best of diets and nutrition, the human body is still lacking in the proper quantity of this conditionally essential amino acid.  In terms of energy, all cells need carbohydrates and fats for energy production.  Even though carbohydrates are converted from glucose to glycogen, your body eventually turns to fat for energy.  This is where L-carnitine as a supplement plays a very important role.  During high energy output, the supply of L-carnitine becomes exhausted.  With the addition of L-carnitine to your supplemental regimen, you body has the ability to use mobilize more fat for energy resulting in greater energy output and increased fat loss which translates to increased weight loss.


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