The dietary supplement L-carnitine is one of the TOP 5 popular sports nutrition supplements. For experienced athletes, L-carnitine is a sports nutrition product that protects the heart during peak exercise, as well as speeds up recovery after competition and shortens the rehabilitation period after injuries. For beginners, it increases endurance, helps to recover faster after training and build lean muscle mass by increasing the absorption of BJU. Well, if you follow the dosage regimen, a low-calorie diet and a weight loss training program, L-carnitine helps get rid of excess fat.

This article is the result of the currently unjustified popularity of L-carnitine as a fat-burning agent with the “you eat it and you start losing everything without diets and training” effect. As a result of the lack of a positive result, many increase the dosage recommended in the instructions, and, as a result, experience all possible side effects. Therefore, let’s talk about why and how L-carnitine helps you lose weight, how to evaluate its use for weight loss as fiction/placebo or reality?

What is L-Carnitine?

Carnitine (C7H15HO3) is a group of varieties of quaternary ammonium cation L-, acetyl-L- and propionyl-L, which are involved in metabolism in humans, mammals, some plants and bacteria, and play a critical role in energy production.

About 95% of the total amount of carnitine present in the human body is stored in skeletal muscle, cardiac muscle, liver and kidneys. 0.5% circulates in the blood, and the excess is excreted in the urine.

Carnitine is sometimes called vitamin B11, and is classified as a conditionally essential micronutrient, since the human body can synthesize it itself. To do this, it needs 2 amino acids – lysine and methionine, as well as iron and vitamins C, B3, B6, B9, B12.

Common dietary sources of L-carnitine

Both a balanced omnivore and a vegetarian or vegan diet provide enough amino acids to synthesize your own carnitine in sufficient quantities. The strictest vegan diet allows the body to produce 14.4 mg/day of carnitine against a requirement of 15 mg/day (self + from food sources).

The most valuable and common sources of L-carnitine in food (per 100 g) are:

  • cooked beef steak – 51-147 mg;
  • finished products and ground beef – 79-90 mg;
  • stewed beef – 45-50 mg;
  • stewed pork – 20-25 mg;
  • bacon – 23.3 mg;
  • stewed turkey – 13-15 mg;
  • cheddar cheese – 4.0 mg;
  • fried cod – 3.6-6.3 mg;
  • baked chicken breast – 2.7-4.5 mg;
  • ice cream – 3.7 mg;
  • milk – 3-4 mg;
  • cottage cheese – 2.7 mg;
  • mushrooms – 2.6 mg;
  • avocado – 2.0 mg
  • grilled asparagus – 0.16 mg;

You can even get a small amount of L-carnitine from whole grain bread. 2 slices contain 0.2 mg. Among plant sources of dietary carnitine, we highlight legumes, buckwheat, rice, pasta, and nuts.

Healthy children and adults do not need to consume the dietary supplement L-carnitine, since the liver and kidneys synthesize enough of it to meet daily needs.

Approximately 54% to 86% of dietary carnitine is absorbed in the small intestine and then enters the bloodstream. The percentage of absorption of dietary supplement L-carnitine is less, only 14%-18%. Of the 4 forms produced today – L-carnitine, L-carnitine tatrat, acetyl-L-carnitine. To improve absorption, its composition is diluted by 30% with a salt of acetic acid.

L-Carnitine: Functions in The Body

The two main functions of L-carnitine in the human body are the transport of long-chain fatty acids into the mitochondria, where fats are oxidized, converted into the energy source ATP, and the removal of certain toxic compounds from the mitochondria.

Carnitine is a reserve source of food fuel. It was discovered in muscle extracts and described in 1905. The molecular structure was created in 1927. The name comes from the Latin word carno, meaning flesh or meat.

Without L-carnitine, the following are impossible: the synthesis of choline necessary for the transmission of nerve impulses, the production of glucose from non-carbohydrates, the production of ketone bodies. A list including 16 more important properties of L-carnitine can be found in the article “L-carnitine and its secret properties not only for sports.” Here we list that due to these properties, and with its effectiveness proven by full-fledged medical studies, taking the dietary supplement L-carnitine is recommended for treatment:

  • respiratory distress in premature infants;
  • anorexia, anemic conditions;;
  • cardiovascular diseases – angina pectoris, coronary artery disease, cardiomyopathy, cardiogenic shock, myocardial infarction;
  • hyperlipidemia;
  • insulin resistance, type 2 diabetes mellitus, painful diabetic neuropathy;
  • problems with peripheral arteries;
  • hyperthyroidism;
  • osteoarthritis;
  • kidney dysfunction, renal failure;
  • fatty liver disease, hepatitis and renal encephalopathy;
  • conditions caused by a weakened immune system;
  • Alzheimer’s disease and dementia;
  • chronic fatigue syndrome;
  • male infertility – to accelerate maturation, increase the number and motility of sperm

For athletes and fitness enthusiasts, the dietary supplement L-carnitine is of interest because during training it preserves muscle glycogen, reduces the accumulation of lactate and saves amino acids as an energy source, making them potentially available for the synthesis of new protein.