L-Carnitine is marketed and described as a safe nutritional supplement that helps melt body fat and build muscle mass. It is particularly popular and used in many fitness and weight loss fitness programs and is a regular ingredient in most energy drinks. Few know, however, what the active substance is and how effective it is.
Carnitine is a compound found in almost every cell of the human body. It is a naturally occurring substance formed by the amino acids lysine and methionine and is responsible for the transport of fatty acids to the mitochondria.
The major action of carnitine is between cell membranes, assisting in the realization of one of the mechanisms of energy production. To a large extent, this occurs in organs where large amounts of fatty acids are used for energy production. These are mainly the muscles and the heart.
In the body, 99% of L-carnitine is located in the intracellular space and the main organs in which it is stored are skeletal muscles. The next highest concentration of L-carnitine in an organ is the liver.
We all know that amino acids build proteins, which in turn are the main building blocks of every cell. But there are also amino acids that are not used in protein synthesis or as neurotransmitters.
An example is Carnitine, a vitamin-like compound that is synthesized by the essential amino acids lysine and methionine in the presence of sufficient amounts of vitamins B3 (niacin), B6 (pyridoxine), B9 (folic acid), B12, vitamin C, and iron.
Like most amino acids, L-carnitine is also found in the foods we eat. Especially in animal products, it is abundant in meat. To a lesser extent, L-carnitine can also be found in milk, and in plant foods the amounts are practically insignificant.
Although we get about 75% of our total L-carnitine per day through our diet, the remaining 25% is synthesized by the body itself. The exception is vegetarians, who manage to get only 10% and synthesize the remaining 90%.
Carnitine is still one of the best selling nutritional supplements to help lose weight and improve athletic performance.
Still, L-carnitine is the first thing that pops into the minds of almost everyone who decides to lose some extra pounds and reduce their subcutaneous fat.
Carnitine is also often used to improve endurance and reduce fatigue during aerobic training. Unfortunately, carnitine also remains one of the substances with the most controversial scientific data behind when it comes to confirming its effectiveness in this context.
Therefore, our focus today will be on the other health benefits that are mentioned on rare occasions. While it may be popular among athletes and people starting a weight loss cycle, here are many of its other potential benefits.
Several studies also show significant potential for L-carnitine in the fight against high blood pressure.
In one study, the combination of 1 g of acetyl-L-carnitine and 400 mg of alpha-lipoic acid resulted in nearly 10 units of decrease in systolic blood pressure in people over 55 years of age with diagnosed ischemic heart disease.
Similar results are seen in younger people suffering from high blood pressure. There has also been a significant improvement in insulin sensitivity.
Carnitine, mostly ALKAR at doses of about 3 grams a day, has been tested in a number of scientific experiments to improve mental capacity and slow cognitive function in elderly Alzheimer’s patients.
While half of the studies show good and statistically significant positive results unfortunately, the other part of the studies find no difference between the groups of people studied.
Studies in both normal and overweight people and people with diabetes have shown a significant effect on insulin sensitivity and glucose uptake by cells. Glucose intake is enhanced by stimulating AMPK.
To improve insulin sensitivity it helps to reduce the amount of acyl and acetyl groups in the cell, whose accumulation has been shown to lead to a decrease in insulin sensitivity.
The reduction of these groups can be accomplished by removing them from the cell, followed by their excretion via urine. A possible mechanism is also the introduction of these groups into the mitochondria, where they can be used during beta-oxidation.
Propionyl-L-carnitine has shown serious positive results in people suffering from intermittent claudication. Prolonged administration of this formulation at doses of about 2-3 grams per day repeatedly indicated an improvement in symptoms. Also, it indicated an increase in the distances that can be walked by patients.
Secondary prevention in people who have experienced a heart attack
People who have myocardial infarction may also benefit from taking a standard dose of about 3-4 grams of L-carnitine a day.
Few studies are showing a significant reduction in mortality in the L-carnitine-treated groups. There is also a decrease in the side effects caused by a heart attack.
In general, L-carnitine is a safe substance and has no side effects at recommended doses. The standard recommended dosage is in the order of 3-4 grams of L-carnitine per day. This amount should be divided into 2-3 doses.
The route of administration and dose is valid for all popular varieties of carnitine. It does not matter if the product is taken in the form of a liquid, capsule, tablet, dragee or powder.
In some people, high intake of L-carnitine may lead to fish odor syndrome. This could be a strange odor in sweat, breath or urine.
The reason for this is the increase in trimethylamine levels in the metabolism of L-carnitine.
In people diagnosed with Hashimoto’s and decreased thyroid function, the intake of L-carnitine is contraindicated. This is because there is evidence to suggest that oral L-carnitine interferes with the entry of thyroid hormones into the cell nucleus.
L-carnitine is also found in some foods in the food additive industry. The highest abundance of L-carnitine is found in red meat and lamb meat. Other sources are chicken, fish, peanut butter, asparagus, avocado, nuts, seeds, legumes.
Wheat also contains small amounts of L-Carnitine. Finally, mushrooms contain about 15mg L-Carnitine per 100g of product. Dairy products contain from 2mg to 10mg per 100g.