L-carnitine, also known as L-carnitine and vitamin BT, the chemical formula is c7h15no3, and the chemical name is (R) - 3-carboxyl-2-hydroxy-n, N, n-trimethylpropyl ammonium hydroxide internal salt. The representative drug is L-carnitine, which is an amino acid that promotes the conversion of fat into energy. It has many physiological functions such as fat oxidative decomposition, weight loss, and anti-fatigue. It is a food additive and is widely used in infant food Diet food, athlete food, nutritional supplements for the middle-aged and elderly, nutritional fortifiers for vegetarians and animal feed additives, etc.
The research and discovery of L-carnitine are relatively late compared with other natural chemicals. In fact, the research began in the early 20th century. At first, two Russians named gulewitsch and krimberg found L-carnitine from meat extract and named it with Latin carnis, which means "animal meat". Since then, scientists from all over the world began to study him deeply. Scientists have achieved remarkable results. In another experiment not long ago, Carter, a researcher at the University of Illinois, confirmed that vitamin BT is carnitine. In 1958, Fritz found that L-carnitine plays an important role in the oxidation of long-chain fatty acids in heart and muscle tissue, which can improve the metabolism of fat β- Oxidative metabolic rate can accelerate the consumption of fat by cells (mitochondria). From then on, it officially opened the research era of L-carnitine in weight loss. In the 1980s, L-carnitine was listed abroad as a commodity and was included in the 22nd edition of USP. Shortly after 1985, the International Nutrition Conference held in Chicago classified L-carnitine as "essential nutrition under specific conditions". Since then, 22 countries and regions in the world have allowed the addition of L-carnitine to infant milk powder to prevent carnitine deficiency. In 1995, the substance officially passed the EU certification, recognizing its importance as an additive in food. With the increasing number of foreign cases of L-carnitine, China also began to study it. In 1996, the 16th National Technical Committee for Food Additive Standardization approved the use of L-carnitine in beverages, milk beverages, biscuits, solid beverages, and milk powder. So far, the research in China began to enter the next stage. In 2003, L-carnitine was recognized as the safest weight-loss nutritional supplement without side effects by the International Obesity Health Organization.
In vivo, the basic function of L-carnitine is to promote the oxidation and energy supply of fatty acids. The metabolic process of fat passes through the mitochondrial membrane. Mitochondria can metabolize fat to release energy and be consumed by the body, but long-chain fatty acids can not pass through this obstacle. L-carnitine is a necessary coenzyme in fat metabolism. It can promote the entry of fatty acids into mitochondria for oxidative decomposition. It is a carrier for the transport of fatty acids. L-carnitine as fatty acid β- The key substances of oxidation and TCA cycle can transfer the residues of excess fatty acids and other fatty acids in the body from outside the mitochondrial membrane to inside the membrane in the form of ester acyl, so as to balance the energy in the cell. Since L-carnitine can promote the oxidation and energy supply of fatty acids through the mitochondrial membrane, it can promote the combustion of fat in the body to provide energy during exercise. At the same time, acetyl coenzyme A, a common product of fatty acids, branched-chain amino acids (leucine, isoleucine, and valine), and glucose oxidation, can also pass through the cell membrane in the form of acetylcarnitine, Promote the oxidation and utilization of acetoacetic acid and play a role in the elimination and utilization of ketones. Therefore, it has the function of promoting the oxidation of three energy nutrients in the body.
Carnitine was used to treat obesity and lose weight in the 1970s. L-carnitine is an excellent active substance for weight loss. It is a normal component of the diet. Its main function is to help long-chain fatty acids to reduce fatty acids β- Oxidation is conducive to the human body's utilization of fat and the human body's utilization of fat, including burning excess fat for energy without side effects on the body. At the same time, pay attention to strengthening exercise and consuming the fat accumulated in the body to reduce weight. It belongs to a weight-loss method without dieting, anorexia, fatigue, and diarrhea. The relevant experimental results showed that under the maintenance of the original living and eating habits, the subjects took L-carnitine continuously according to the specified dose of health products for 35 days. The results showed that the subjects' weight, waist circumference, hip circumference, total body fat, and subcutaneous fat thickness at all points decreased, and the exercise endurance of the subjects did not decrease after the test. There were no abnormalities in the clinical symptoms and indexes of the subjects before and after the test, It also fully proves the effect in the treatment of obesity.
L-carnitine is harmless to the human body and has such a good effect in treating obesity. At ordinary times, we should deliberately supplement some of the substances to avoid obesity and change the daily diet first. L-carnitine naturally exists in all kinds of meat and milk. Animal foods have high content. Foods with rich content include yeast, whey, liver, lean meat, heart, mutton, chicken, rabbit, and milk. It is reported that 0.6 g crystalline carnitine can be extracted from 450 g beef extract and 100 g lactose powder containing 2% L-carnitine can be extracted from 56 kg milk. For vegetarians, this method is not desirable, so we also sorted out the content of plants, but the content of L-carnitine in plant food is relatively low compared with that in animals. At the same time, the content of lysine and methionine, two essential amino acids for carnitine synthesis, is also low, avocado, kiwi fruit, raisin, papaya, lemon, aloe It is found in Alpine fruits such as lotus leaf and malt. Therefore, in the ordinary diet, we can eat more such substances to enhance our physique, supplement nutrients and prevent obesity.