L-carnitine is synthesised from the amino acids lysine and methionine, and it performs essential functions in human metabolism. The naturally occurring protein compound does this by acting as a receptor molecule for different fatty acids.
It therefore contributes towards providing an effective supply of nutrients and energy generation in the body.
The importance of L-carnitine is particularly clear in the transport of fatty acids. Long-chain fatty acids are only able to be transported into the mitochondria, which generate energy in the cells of the body, with the help of L-carnitine. Therefore carnitine is particularly well known as a fat burner.
Because the human body can build L-carnitine itself, only part of the daily requirement for the substance must come from the intake of food. The fact that human cells mostly absorb the protein-like substance through eating meat must also be taken into account when considering the required daily intake. This is because larger amounts of L-carnitine are present in mutton and lamb, so the intake requirements can be met more easily with suitable consumption of these products.
Most important properties:
- It is the transport molecule for fatty acids
- It can improve the process of burning fat, and it can help you lose weight
- It can allow better energy release (which is recommended in order to meet cognitive performance requirements)
- It improves recovery after sports
- There is some evidence to suggest that L-carnitine can improve erectile function and sperm production (however, the results of studies on L-Arginine are more convincing).
L-carnitine occurrs mainly in red meat (beef, lamb), in small amounts also in white meat (chicken, turkey).
Only very small quantities are found in vegetarian foods. Vegetarians and Vegans thus usually have very low L-carnitine levels.
It is most sensible as a food supplement for people, who are mentally and physically very active, on a diet or vegetarians.
- 300 mg – 500 mg when normally fatigued
- 750 mg bis 2,000 mg during fat loss
- 1,500 mg – 3,000 mg to improve the erection.
No side effects are known.
Even extremely high dosages of 15,000 mg per day do not have an impact on the body.
In the past however, very low quality L-carnitine has been found in supplements distributed by asian online pharmacies. These supplements are know to have cause complications. Consumer should therefore ensure the quality and origin of the product at hand.
Products with L-carnitine should ideally be produced of pharmaceutical grade Carnipure®.
Combine L-carnitine with other Vitamins, coenzyme Q10 und minerals to increase the effect.
Products, which include Carnipure® and purchased at pharmacies are recommended for their quality.
On average the body contains 20-25g of L-carnitine, which is mostly stored in heart muscles and skeletal muscles.
These muscles are characterised by their intensive metabolism of fatty acids, and they are therefore particularly dependent on proteins.
One of the most important properties of L-carnitine is its ability to exist redundantly when present in the human body, without causing significant adverse effects. It can be converted into urea, and then excreted in urine without causing health problems. Because of this, a possible overdose of L-carnitine leads to no side effects or other damage.
In contrast to this, there are some diseases such as Crohn’s disease, where an additional supply of the nutrient through supplements is very important in managing the condition.
How does L-carnitine work?
The physiological process of how L-carnitine is used on the body to transport fatty acids into the mitochondria for energy generation is described in this excellent video (from 1:20).
Foods that are rich in L-carnitine
L-carnitine is a water-soluble molecule and it can therefore be naturally excreted through the production of urine. Because of this property, the amount of L-carnitine present in patients undergoing dialysis treatment is frequently too low. As a result of this, the patients must take additional supplements or be supplied with L-carnitine intravenously. During the dialysis treatment, the nutrient is removed from the body alongside other compounds usually eliminated in the urine. Consequently, this can lead to the development of a deficiency.
Furthermore, the high solubility of L-carnitinein water can have a negative effect on the contents of certain food products after cooking. This is because after prolonged contact with water, a leaching effect can occur and the quantities present can become considerably reduced.
Very little L-carnitine is present in vegetarian food
The human body mostly receives its supply of L-carnitine from red meat. Because of this, in a mixed diet around 100 to 300 mg per day is taken into the body. Conversely fruit, vegetables and meat from poultry contain little or no L-carnitine. Therefore, people following a vegetarian or vegan diet receive only approximately 3 – 20% of the level received through a mixed diet, and this amount of L-carnitine is classed as being inadequate. 1.
In addition to the intake of L-carnitine in the diet, the substance is also synthesised by the body. However different vitamins and iron must also be present in adequate quantities for this to occur. If this is not the case, the production continuously slows down until it finally becomes essential that the nutrient is supplied through particular foods.
In order to do this, almost all types of meat can be used and mushrooms also contain a substantial amount (approximately 15 mg per 100g). Products that are particularly suitable for vegetarians to eat in order to meet the daily requirements include cheese (approximately 0.6 to 12.7 mg per 100g) and dairy products (approximately 2 to 10 mg per 100g). However, it must also be taken into account that only 54 to 87% of food consumed contains L-carnitine that is available for the body to use and which can be recycled.
Functions of L-carnitine
L-carnitine fulfils essential functions in the body as a vitamin-like substance, and in doing so it is involved in a variety of processes. For example, it supports the kidneys and liver in their role in detoxifying substances and eliminating these toxins. It also enables the burning of long-chain fatty acids in order to release energy.
This is required by a range of muscle cells in the human body, but particularly by those in the heart. Furthermore in all the sites where this is possible, L-carnitine fulfils its function as a so-called ‘bio carrier’ by directing fatty acids to the site of energy production inside the membrane of the mitochondria.
The reserves of L-carnitine in the human body are relatively small- they only consist of approximately 20 to 25 mg. Therefore insufficient intake of food can be very quickly noticed and this can lead to the occurrence of dangerous symptoms of deficiency. These are frequently expressed through an increased susceptibility to infections, disorders of lipid metabolism or reduced fertility.
An insufficient supply of L-carnitine also increases the risk of having a heart attack, as the heart muscle is heavily dependent on the presence of an adequate level of the nutrient.
Supporting the immune system
Another important application of L-carnitine is in supporting the immune system. With the help of lymphocytes pathogens can be rendered harmless, and this process is stimulated by the vitamin-like substance, L-carnitine. Therefore with the help of L-carnitine, the immune system can be strengthened and illnesses can be more easily fought off. Furthermore, the nutrient can increase the activity of phagocytic cells and killer cells, and L-carnitine itself can also function as an effective antioxidant. In this context, it inhibits the destruction of cells and tissues due to so-called free radicals, and as a consequence mostly protects membranes and nerve cells. For this reason, to some extent L-carnitine can also protect against degenerative neurological diseases such as Alzheimer’s and Parkinson’s disease, as these are associated with the increasing degradation of neurones.
Finally, a sufficient supply of the vitamin-like substance can lead to improved physical and mental performance. For this reason, L-carnitine can also be used for targeted performance enhancement in athletes. It reduces the recovery time required for greater physical exertion, and equally helps with the elimination of unwanted fat deposits.
L-carnitine use against diabetes
In most cases patients with diabetes struggle with heightened oxidative stress, and it has been found that with L-carnitine these high levels can become reduced. Because of this possible link, in 2008 a study was implemented to investigate this relationship, where in over 80 subjects the effects of supplements containing L-carnitine were examined. The investigation showed that the supplements could reduce the concentration of both LDL cholesterol and triglycerides, and could therefore decrease the level of oxidative stress. 2.
L-carnitine encourages the burning of fat
L-carnitine is essential in the burning of lipids and it is also involved in supplying energy to muscles. Therefore, it can contribute towards targeted fat reduction within the framework of dietary measures. Additionally, L-carnitine increases the development of muscle mass with suitable supplementation, and it promotes a positive state of mind. Furthermore, it can reduce fatigue in older people, and lead to increased vitality and energy. 3.
The effect of L-carnitine on heart disease must also not be underestimated, as it generates approximately 70% of the energy required by the heart. For this reason, the vitamin-like substance supports heart function for existing limitations such as angina or coronary sclerosis, and can consequently protect against possible exacerbations or heart attacks. Cardiac arrhythmias can also be avoided with suitable supplementation and the characteristics of an existing heart failure can be alleviated. 4.
L-carnitine boosts male fertility
Carnitine has been found particularly useful in improving male fertility. Indeed, it supports many critical sperm quality factors simultaneously such as sperm count and concentration5, motility6, nuclear DNA integrity, and morphology7.
Please watch the following video on how Carnitine and other nutrients from food can improve the quality of sperm naturally.
L-carnitine is produced in the body from two essential amino acids. However despite this, a proportion of our daily requirements for the nutrient need to be met through our food intake, and because of this particularly vegetarians and vegans have insufficient levels of L-carnitine. Additionally, too much stress together with pre-existing conditions and disorders of absorption can contribute towards a deficiency and inhibit some areas of metabolism.
L-carnitine not only controls the metabolism of fat, but it is also responsible for the protection of nerve cells and cell membranes. For this reason, it can be regarded as vital for maintaining the health of the body. In addition to this it is an essential component of orthomolecular medicine, and as an excess supply of L-carnitine can easily be excreted through urine, even in very high doses no side effects are expected.
- “Axel G. Feller and Daniel Rudman: Role of carnitine in human nutrition. In: The Journal of nutrition, Volume 118, Issue 5, 541 – 547, Januar 1988” ↩
- “Malaguarnera M et al.: L-carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes; Am J Clin Nutr. 2008 Dec 3″ ↩
- “M. Malagurnera et al.: L-carnitine treatment reduces severity of physical and mental fatigue and inreases cognitive functions: a randomized an controlled clinical trial; American Journal of Clinical Nutrition; Vol. 86, No. 6, 1738-1744 Dec. 2007” ↩
- “Serati AR, Motamedi MR, Emami S, Varedi P, Movahed MR. L-carnitine treatment in patients with mild diastolic heart failure is associated with improvement in diastolic function and symptoms. Cardiology. 2010;116(3):178-82” ↩
- “Mataliotakis, I. et.al. (2000). L-Carnitine levels in the seminal plasma of fertile and infertile men: correlation with sperm quality. International Journal Fertility and Women’s Medicine, Volume 45, Issue 3, (pp. 236-240)” ↩
- “Balercia, M. et.al. (2005). Placebo-controlled double-blind randomized trial on the use of l-carnitine, l-acetylcarnitine, or combined l-carnitine and l-acetylcarnitine in men with idiopathic asthenozoospermia. Fertility and Sterility, Volume 84, Issue 3. (pp. 662-671)” ↩
- “Banihani S. et.al. (2012). Human sperm DNA oxidation, motility and viability in the presence of L-carnitine during in vitro incubation and centrifugation. Andrologia, Volume 44, Issue 1, (pp. 505-12)” ↩