03/16/2023
Amino acids are defined as “the building blocks of proteins”, they are also the result from the digestion of proteins. There are 22 amino acids that are required by the human body to create human proteins, and these aminos must be placed in a particular pattern. Fourteen of these are considered non-essential (as the body can manufacture them); eight are referred to as “essential”, meaning that they must be obtained from food and/or supplements.
One such non-essential amino acid is L-carnitine. It is found mainly in the heart and skeletal muscle, and more specifically in the mitochondria (“the powerhouse of the cell”) where it is utilized in employment of fats called beta-oxidation.
Essential fats cannot pe*****te the inner membrane of a mitochondria without a transporter - this is where l-carnitine comes in. L-carnitine utilizes at least three different enzymes in the process, and the success of the aforementioned beta-oxidation process is then determined by not only the transport system itself, but how much carnitine is available for use. Obviously, higher levels of l-carnitine will increase the beta-oxidation while lower levels slow it down.
Regarding weight loss, you want your body to switch from utilizing carbohydrates for energy to using stored fat. For this to occur, you will need a steady and adequate supply of l-carnitine to transport the stored fat into the mitochondria. Now, if you are overweight, your body does not create as much of this amino acid; therefore, you will need to supplement. (Note: exercise is a MUST when adding in l-carnitine for weight loss.). New studies are being done to show that in women diagnosed with PCOS, a deficiency of l-carnitine has been noted.
Another benefit of this amino acid is that it has the backing of multiple studies to show its effectiveness in reducing fat accumulation in the blood and tissues, a major symptom of cardiovascular disease. (This in no way is to be a substitute for a healthy, cardiometabolic diet and exercise program, but rather as a supplement.) Studies showing that a minimum dose of 2000 mg daily helped to reduce the amount of heart attacks in persons with CVD, and at a dose of 3000 mg, it helped these patients to improve their exercise performance. Another groundbreaking study even reported that in patients who were taking anti-arrythmic drugs, supplementing with l-carnitine improved the efficacy of these drugs.
If you have hypothyroidism, be wary of l-carnitine as it can prevent thyroid hormone from getting into the cells; on the other hand, this mechanism of action may help to diminish symptoms of hyperthyroidism. If you are taking anticoagulants or blood pressure medication, please check with your functional medicine provider prior to taking l-carnitine.
There is some proof that l-carnitine may protect against the toxic effects of doxorubicin (a chemotherapy agent) without lessening the efficacy of the drug.
Also, please remember that dietary supplements are there to help supplement the diet (hence the name!) There is absolutely nothing that can take the place of a healthy diet, daily exercise and proper sleep.
Kelly Sieberg, Integrative Health Practitioner and Functional Medicine Certfiied Health Coach
Standard disclaimer: These statements have not been evaluated by the Food and Drug Administration. The information provided here, although backed by research, is not intended to diagnose, treat, cure, or prevent any disease.
References (some abstracts noted):
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Fatih Celik, Mesut Kose, Mehmet Yilmazer, Gülengül N. Köken, Dagistan Tolga Arioz & Mine Kanat Pektas (2017) Plasma L-carnitine levels of obese and non-obese polycystic o***y syndrome patients, Journal of Obstetrics and Gynaecology, 37:4, 476-479, DOI: 10.1080/01443615.2016.1264375
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DiNicolantonio, J, Lavie C, Farres H, Menezes A, O’Keefe, J. L-carnitine in the secondary prevention of cardiovascular disease: Systematic review and meta-analysis. Mayo Clinic Proceedings 2013 April 17. 88; 6, 544-551. doi.org/10.1016/j.mayocp.2013.02.007
Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A. Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis. Clin Nutr ESPEN. 2020 Jun;37:9-23. doi: 10.1016/j.clnesp.2020.03.008. Epub 2020 Apr 18.
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Xiapoing, L, Reichetzer B, Trines J, Benson L, Lehotay D. L-carnitine attenuates doxorubicin-induced lipid peroxidation in rats. 1999 Free Radical Biology and Medicine; 26(9-10). 1158-1165