L-Carnitine

L-Carnitine and the immune system

L-carnitine is a vitamin-like and conditionally essential nutrient. The main sources of L-carnitine are meat, fish products, milk and breast milk. L-carnitine as an endogenous substance enables the transport of long-chain fatty acids into the mitochondria and is used for energy production. The human body contains about 20-25 g of L-carnitine. Particularly rich in L-carnitine are the heart, muscle and immune system, which have a particularly high energy requirement and thus depend on a sufficient supply of L-carnitine.

Importance for the immune system

The human immune system is composed of a multitude of different cells and substances, which in their entirety form the complex protective system of our body. Millions of specialized cells ensure that the organism performs its functions undisturbed and is not impaired by foreign bodies. Immunological processes are always characterized by a high rate of cell division and synthesis. They therefore also require a constant supply of energy. In addition, membrane-associated processes are also involved. The high L-carnitine content of leukocytes is an indication of the essential role of L-carnitine for energy production as well as for optimal membrane function and cellular metabolism. Within the dynamic structure of the immune system, L-carnitine fulfills various tasks:

• For the immune system it is essential to use fatty acids energetically. Since L-carnitine transports long-chain fatty acids into the mitochondria, it can certainly be called the "motor" of the immune system.
• In addition, L-carnitine protects cell membranes from the damaging effects of activated fatty acids. Damaged membranes endanger the osmotic balance, increase the energy demand and reduce the synthesis performance of the cells.

L-carnitine as an immune stimulant

Experimental results confirm that L-carnitine acts as a natural immune stimulant. In the case of deficiency symptoms caused, for example, by stress or sporting activity, compensation can be achieved through food containing L-carnitine (e.g. probiotic drink "Vollfit", fitness bar). The immune system is made fit, so to speak. Highly pure, synthesized L-carnitine, as produced by Lonza, is equivalent to the body's own natural nutrient.

The immune cells absorb as much L-carnitine from the blood as they need for their optimal activity, overloading of the system is excluded. L-carnitine is therefore also used with success in cases where other (herbal) immune stimulants are contraindicated, such as in acute infections like sepsis, in fever and burns.

The body benefits overall

L-carnitine's positive effect on the immune system can of course be extended to the entire human organism. A study by Cerretelli and Marconi in 1990 showed that the intake of L-carnitine increased the overall concentration level in muscle cells and that study subjects walked longer distances on average. It can be concluded that L-carnitine has a positive effect on fitness. Positive effects on the cardiovascular system were also observed. L-carnitine strengthens the heart muscles and can thus contribute to a reduction in the risk of heart attack. The broad therapeutic spectrum shows the nutrition-specific importance of L-carnitine. The daily requirement of L-carnitine is between 200 and 1200 mg, depending on the physical strain.

Performance enhancement through L-Carnitine

Critics of L-carnitine often talk about the lack of studies on the effectiveness of the vitaminoid. In fact, numerous independent studies exist. The studies prove that L-carnitine measurably improves physical performance and regeneration and boosts both cardiac output and metabolism. Performance-enhancing effects from administration of L-carnitine have been observed in over 40 studies. The most recent study on performance enhancement by L-carnitine took place at the University of Basel under the direction of Prof. Walter. The performance of cyclists was tested in several runs. On average, their performance with L-carnitine was between 11% and 19% higher than with placebo in all runs. Accelerated recovery and increase in strength occurred equally in untrained and trained test subjects. The increase in performance due to L-carnitine is a kind of "training effect from within" and is within a physiological range. Today, L-carnitine is one of the standard products of sports nutrition. Not only the performance of athletes can be positively influenced by L-carnitine. L-carnitine has also been shown to measurably increase physical performance in heart patients, dialysis patients, people with circulatory disorders and post-polio patients. L-carnitine therapy for poliomyelitis is recommended by the Polio Association and reimbursed by health insurance companies.

How does L-Carnitine work?

L-carnitine is a vitamin-like and conditionally essential nutrient. It plays a key role in the body's energy balance by significantly supporting the transport of long-chain fatty acids into the mitochondria. There, the fatty acids are broken down and released in the form of energy. In addition, L-carnitine facilitates oxygen uptake during physical exertion. A sufficient supply of L-carnitine ensures that the muscles and cardiovascular system do not tire as quickly. The immune system is also strengthened, the defense cells are more active and more eager to attack.

Who can benefit?

Generally speaking, anyone who is exposed to particular stresses can benefit from L-carnitine. This applies to people who suffer from muscle weakness or lack of concentration as well as athletes whose muscles are exposed to continuous stress. People under stress also need sufficient L-carnitine. As part of a diet, the nutrient can accelerate fat loss in combination with endurance training.

The main sources of L-carnitine are meat, fish products, milk and breast milk. Vegetarians and vegans in particular therefore often have a deficiency that can be covered by synthetically produced L-carnitine. This is available in foods such as bars, drinks or probiotic drinks in supermarkets and fitness studios or as a dietary supplement in pharmacies, health food stores and fitness studios.

Tired men - lively thanks to L-carnitine

Men are more careless with their bodies than women - this has been proven by scientific studies. The male body has enough to suffer and deserves significantly more attention and care if it is to remain healthy and efficient and "stand its ground". If it is neglected, however, it takes revenge with exhaustion and listlessness. What makes tired men feel better? Milk alone is seldom enough to revive tired men's spirits. L-carnitine, which supplies the body with new energy, is a better solution.

On average, men in the Western world die seven years earlier than women. This is no coincidence: the stronger sex is significantly more careless with its body. Men eat an unhealthier diet, go to the doctor less often and consume more nicotine and alcohol than is good for them. These risk factors, combined with stress and too little exercise, sap male strength and make them susceptible to illnesses of all kinds. Fatigue, tiredness, listlessness: almost every man suffers from this. But men can easily do something for their health: The daily intake of 1-3 grams of pure L-carnitine can help to boost the functions of the organism and overcome the low.

L-carnitine is a vitamin-like nutrient that is partly produced by the body itself, but two-thirds of which must be supplied externally through food or supplementary products. The daily requirement is between 200 and 1200 mg, depending on the physical load. Muscles, the immune system and the heart are particularly dependent on an adequate supply of L-carnitine. L-carnitine plays an important role in energy metabolism and fat burning. It enables the transport of long-chain fatty acids into the mitochondria, where energy is obtained from them.

Sufficient L-carnitine ensures that the muscles do not tire so quickly - a bar with L-carnitine before sports is enough to increase performance and endurance. The same applies to the heart and immune system, where the defense cells are strengthened. So the man can be helped: A dietary supplement with L-carnitine supports the body during exertion, stress and immune deficiency. And tired men are finally a thing of the past.

L-carnitine: synthesis and deficiency symptoms

The body's own L-carnitine synthesis is primarily carried out by the liver. Studies show that the kidneys and brain also produce L-carnitine, but only in minimal quantities. The synthesis of L-carnitine relies on the "cooperation" of various other substances such as vitamin C, B3, B6, B12, folic acid, iron, and the amino acids lysine and methionine. Although an undersupply of one or another micronutrient impairs L-carnitine synthesis, a vitamin C deficiency is most quickly noticeable. The body's own carnitine synthesis covers about 10% of the total L-carnitine requirement.

Since the ability to synthesize L-carnitine is not fully developed until the age of 15, attention must be paid to carnitine-rich foods, especially when feeding children. Due to its involvement in fat metabolism, L-carnitine is mainly found in muscle meat. This is not only true for L-carnitine sources from food, but also for the human organism. These figures underline how important L-carnitine is for the performance of the muscles. The body's own synthesis of L-carnitine is not able to adapt to an increased demand. It proceeds rather slowly and is dependent on a large number of other substances. If an increased demand arises as a result of increased physical activity, this can only be covered by additional L-carnitine ingested with food.

Signs and risks of L-carnitine deficiency

Since L-carnitine as a so-called "biocarrier" makes an essential contribution to the energy production of the body, is involved in detoxification processes and takes over the removal of activated fatty acids within the framework of ?-oxidation, various causes arise in the case of insufficient supply of L-carnitine.

• Reduced biosynthetic capacity
• lower absorption in the intestine
• Reduction of L-carnitine transport through the cell membrane
• increased excretion by the kidney
• increased demand (in case of physical strain or extraordinary stress)

Primary, secondary and functional L-carnitine deficiency

A distinction is made between primary and secondary L-carnitine deficiency. Under the designation of the primary deficiency, congenital, or inherited disorders are summarized, which in turn are assigned to the myopathic or systemic form.

Primary deficiency - myopathic form

Disorders of the myopathic form primarily affect the muscles. Clinically, the focus is usually on blatant muscle weakness. Measurements of the L-carnitine concentration in the blood plasma have shown that there is no recognizable deficiency. It is therefore assumed that the L-carnitine deficiency is due to a transport disorder in the mitochondrial space.

Primary deficiency - systemic form

In the systemic form, myocardiopathy, encephalopathy (non-inflammatory diseases of the brain), hyperammonemia (increased ammonia concentration in the blood) and other disorders can be detected in addition to muscle weakness. If these primary carnitine deficiencies of the systemic form occur in the first months or years of life, they can even lead to death.

Secondary and functional L-carnitine deficiency

Secondary carnitine deficiency refers to disorders that are caused by a secondary cause and usually occur in the course of life and are not congenital. Such deficiencies occur, for example, as a result of reduced intake or increased consumption or demand, or as a result of disease or drug treatment. A functional L-carnitine deficiency is characterized by an insufficient availability of free L-carnitine and leads to performance limitations.Main causes of a secondary L-carnitine deficiency are:

• vegetarian lifestyle: Very little or no L-carnitine is found in plant products. Vegetarians therefore consume only 10-20% of the amount contained in a standard national mixed diet.
• Age: Over the years, the body's own L-carnitine biosynthesis slows down. Current studies suggest that the free radicals generated during -oxidation damage the mitochondrial system and thus accelerate its aging process.
• Impaired absorption: L-carnitine is absorbed in the small intestine. In children suffering from celiac disease (digestive insufficiency due to gliadin intolerance), severely reduced L-carnitine levels can therefore be detected.
• Renal loss and dialysis: In chronic renal insufficiency, there is an increased excretion of L-carnitine via the kidneys. However, renal loss does not only occur in the context of renal insufficiency. It can also be detected after burns, major surgical interventions and in malignant diseases. Dialysis leads to greatly increased L-carnitine losses of up to 85 % of the plasma content.
• Pregnancy: Of course, we should not talk about a disorder in this context, but reduced carnitine levels by up to 50% can also be observed in the context of pregnancy.
• Fasting and parenteral nutrition: In these special cases, the supply of L-carnitine via food is interrupted. In tube feeding, however, L-carnitine can be added to the preparations.
• Oxygen deficiency: Oxygen deficiency, whether caused by a reduced supply, e.g. in the case of vasoconstriction, or by a sharp increase in oxygen demand as a result of vigorous physical activity (e.g. sport), leads to a reduction in the availability of free L-carnitine.

Get to grips with spring fatigue

Every year, with the first spring greenery, the big yawn also spreads: 80-90% of the population are affected by spring fatigue. The seasonal change in weather causes our bodies to struggle. Exercise in the fresh air helps against this. In addition, a diet containing L-carnitine can strengthen the circulation. A positive side effect is that L-carnitine promotes muscle growth and helps to shed pounds accumulated over the winter. A number of scientific studies support this: Gross (1998), Bradley (1996) and Ahmad S et Al (1990) demonstrated that the vitamin-like nutrient L-carnitine promotes the breakdown of the body's own fat in the long term and supports the build-up of lean muscle mass.

While nature gets really active outside, the big yawn spreads in many places in spring. Springtime fatigue strikes. According to surveys, well over half of Germans suffer from this phenomenon. Typical symptoms are circulatory problems, fatigue, increased susceptibility to colds and poor performance. Exercise in the fresh air is the best remedy for springtime fatigue. Spring walks are just as suitable as cycling or a tennis match. Exercise boosts circulation and fat burning. In order to support muscle building and fat loss, sufficient L-carnitine supplementation should also be taken into account in the diet.

Studies conducted by Gross, Jewell and Bradley on seven animal species - including dogs, cats and fish - showed that the administration of L-carnitine reduces body fat and increases lean muscle mass. The scientists Ahmad, Spagnoli and Wohlers also demonstrated that the muscle-building and muscle-maintaining effects of L-carnitine also apply to humans. L-carnitine is a vitaminoid that plays a key role in fat metabolism. It transports fatty acids from the blood into the muscle cells, in the mitochondria the fat is burned and energy is released. Thus, L-carnitine supports the reduction of body fat.

The daily requirement of L-carnitine is between 200 and 1200 milligrams, depending on the physical strain. In spring, not only figure-conscious people should pay attention to a sufficient dietary supplementation with L-carnitine. Especially people who are plagued by spring fatigue can counteract the premature fatigue of muscles and cardiovascular system with the help of L-carnitine. Foods such as crab or mutton provide natural L-carnitine. In concentrated form, the nutrient is available in bars, tablets, capsules, chewing gum or probiotic drinks. Combined with outdoor exercise, it's a sure way to feel better about your body - and summer can come.

L-carnitine positively influences fertility

High environmental pollution, stress, poor diet - the reasons for involuntary childlessness are manifold. One of the main causes is the steadily decreasing sperm quality in men. A deficiency of essential nutrients such as L-carnitine is often observed in this context.

A growing percentage of couples remain involuntarily childless.

According to estimates, in around 40% of cases this is due to the man's poor sperm quality (lack of motility and number of sperm). The cause is often a deficiency of L-carnitine: in studies, infertile patients often had significantly low L-carnitine levels. L-carnitine deficiency can also have a negative effect in women: Women with severe complications in pregnancy have 73% low L-carnitine levels.

L-Carnitine in the human body

Human organs such as muscles and heart contain L-carnitine. The organism produces the nutrient itself in part, but in the main it is supplied through food (meat and dairy products are particularly rich in L-carnitine). Sperm cells are the cells in the male body richest in L-carnitine, they contain about 2000 times more L-carnitine than blood. In the form of acetyl-L-carnitine, the nutrient serves the sperm as an energy source on the way to the egg cell.

L-Carnitine during pregnancy

A positive effect of L-carnitine is observed in pregnant women: Thus, 2 g of L-carnitine per day normalizes the level of free fatty acids in plasma, reducing the risk of gestational diabetes. The embryo also benefits from L-carnitine administration: lung maturation is accelerated and lung function is better in children after birth. The positive effect of the nutrient is also used in animals: In the U.S., L-carnitine is given to sows at the beginning of pregnancy in more than 40% of cases (and increasingly also in Europe), as piglets are stronger and gain weight faster after birth as a result. It also reduces the number of piglets born weak for life.

Possibilities and limits of L-carnitine

Studies have shown that L-carnitine has a positive influence on male fertility, as the administration of 3 g L-carnitine per day after three to four months causes a significant increase in sperm count, quality and motility. As a caveat, infertility is a medical condition that requires medical treatment. L-carnitine is not a drug and therefore not recommended for treatment. However, it has been proven that the reproductive capacity of people with a balanced diet is the highest - therefore, in case of deficiency, supplementation with L-carnitine is recommended.

L-carnitine is power for the weak heart L-carnitine ensures a better supply of poorly perfused hearts

People with poor blood circulation to the heart can reduce the risk of developing secondary diseases such as chronic cardiac insufficiency, angina pectoris or a heart attack by taking L-carnitine. Due to these disorders, the adequate supply of blood to the heart is not guaranteed. This results in a lack of oxygen and nutrients in the heart. The additional administration of L-carnitine, a vital amino acid compound, can improve the deficiency. To improve the energetic situation and the performance of the heart, an additional intake of one to two grams of L-carnitine per day was found to be effective in various studies (1,2,3).

This improvement is explained by the function of L-carnitine to transport free fatty acids, which serve as the most important energy suppliers of the heart muscle, into the mitochondria. Mitochondria are "power plants" inside the cell that produce energy by burning fatty acids. Furthermore, L-carnitine serves to detoxify metabolic products and toxins that occur in the heart when there is a lack of oxygen and substrates. An optimally supplied heart muscle does not get sick so easily and is more efficient. Healthy people produce L-carnitine in sufficient quantities to meet their daily needs in the liver, kidneys and brain from the amino acids L-lysine and L-methionine. In food, it is particularly abundant in lamb, beef and pork.

Demand in sport

I have read many reports that increased carnitine intake or supplementation does not help with fat burning. Or that healthy people who have normal carnitine levels do not benefit at all from supplementation, because the carnitine concentration in the muscle itself does not change.

In the liver, L-carnitine is broken down and transported from there to other body tissues that use fatty acids as primary fuel, such as skeletal muscle and cardiac muscle. Once there, carnitine first dissolves the fat out of the tissues and causes its conversion into fuel. It then removes the troublesome by-products of fat metabolism from the mitochondrial matrix to prevent their accumulation and the formation of new fats.

All this would not be the case with a carnitine deficiency. This does not mean that you effectively gain fat with a carnitine deficiency, but the metabolism would slow down rapidly and thus also the fat burning. This can also be the case with healthy people, for example, in very high stress situations or with a deficient diet (carnitine deficiency). It is very difficult, even as a healthy person, to have a constant carnitine concentration in the muscle or even impossible. That is why it is so important to supplement carnitine, so that it is always available in sufficient quantity and also never to get into such a situation.

No one has claimed that carnitine is the miracle cure for fat deposits but one should keep in mind that high carnitine amounts accelerate fat burning but low or even deficient amounts slow it down. This would be a nightmare for any athlete. No matter what vehicles you use to condition your body, whether aerobic training, fasting, supplements, drugs, weight training, diets or anabolic steroids, etc., as long as carnitine cannot fully exert its effect because it is not sufficiently available in the body, the fatty acids cannot penetrate the fat burning matrix and consequently cannot be burned.

You need to give your body a chance to fight back against the 30 billion fat cells by targeting your carnitine-dependent fat burning matrix through regular and smart carnitine supplementation. According to recent studies, 1-4g of carnitine a day supports effective functioning of this shuttle system and reduces the buildup of blood triglycerides. The production of fat from dietary calories is called lipogenesis. In addition, carnitine has numerous other benefits and therefore indispensable for us athletes:

• Under extreme stress, increases the concentration of pyruvate ATP and creatine phosphate in parts of the heart muscles
• Supports normal blood circulation by improving peripheral circulation
• Makes muscles more resistant to fatigue.
• Supports fatty acid and carbohydrate metabolism
• Protects the vascular walls from a lack of oxygen
• Provides more energy for the heart and thus improves its performance
• Prevents cardiac arrhythmias
• Reduces the occurrence of triglycerides, increases the good HDL cholesterol
• Improves amino acid metabolism in skeletal muscles during long periods of training or fasting when dietary fats or carbohydrates are scarce
• Raises the general energy level.

L-Carnitine and Ketosis

The advocates of ketogenic (low-carb) diets claim that if it did not have enough carbohydrates available as fuel, the body would resort to other sources of energy, namely stored body fat. However, if such diets are not strictly monitored, especially in diabetics, it can lead to hyperacidification of the blood by the released ketones and thus to excessive excretion of important electrolytes. This situation, in the absence of observation, can get out of hand and become life-threatening. It is now known that carnitine, with its fat-burning properties, prevents the accumulation of ketones in the body. Therefore, those who follow the Aktis or abdere low-carb diet basically benefit from carnitine supplementation.

L-Carnitine, better regeneration and muscle contractions.

Carnitine is not only responsible for the transport of long-chain fatty acids into the mitochondria. Bodybuilders appreciate it above all because it accelerates their regeneration after hard training sessions. In one study, 10 healthy recreational bodybuilders took two grams of carnitine a day for three weeks. The men completed a squat program consisting of five sets of 15 to 20 repetitions, once under the influence of placebo and once under the influence of carnitine. The difference in muscle damage was unmistakable: 16 to 23 percent (carnitine) versus 29 to 39 percent (placebo).

Dosage

My recommendation is to take 2-4g per day of carnitine on an empty stomach. This amount should be distributed over two to three intakes. I hope that I have presented a sufficient overview of this supplement.

Safety and side effects

L-carnitine is probably safe and harmless for most people when taken orally. It is also safe and harmless as an injection after clearance by a physician. L-carnitine may cause some side effects such as nausea, vomiting, stomach upset, heartburn, diarrhea and seizures. It may also cause a fish-like odor from urine, breath, and sweat. L-carnitine may be safe and harmless for children when taken appropriately for short periods of time.

Precautions and Warnings:

Pregnancy and lactation: Not enough is known about the safety and harmlessness of L-carnitine during pregnancy, so pregnant women should avoid L-carnitine to be on the safe side. Taking L-carnitine in appropriate amounts may be safe and harmless for breastfeeding women. Small amounts of L-carnitine have been administered in breast milk or infant formula to infants with no reported adverse effects.

The effects of taking large amounts of L-carnitine on breastfeeding women are not known. Hypothyroidism: Taking L-carnitine could worsen symptoms of hypothyroidism. Seizures: L-carnitine seems to make the occurrence of seizures more likely in people who have had seizures in the past. For this reason, L-carnitine should not be used if you have ever had a seizure.

Drug interactions:

Care should be taken when combining L-carnitine with the following medications:

Acenocoumarol

Acenocoumarol is used to slow down blood clotting. L-carnitine could enhance the effect of acenocoumarol. Enhancing the effect of acenocoumarol could slow down blood clotting too much. Acenocoumarol dosage may need to be adjusted when taking L-carnitine.

Thyroid hormones

L-carnitine seems to reduce the effect of thyroid hormones. Taking L-carnitine in combination with thyroid hormones could reduce the effectiveness of thyroid hormones.

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