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. As an endogenous substance, L-carnitine enables the transport of long-chain fatty acids into the mitochondria and is used for energy production. The human body contains approx. 20-25 g of L-carnitine. The heart, muscles and immune system are particularly rich in L-carnitine, as they have a particularly high energy requirement and are therefore dependent on a sufficient supply of L-carnitine.

Importance for the immune system

The human immune system is made up of a large number of different cells and substances, which together 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 a sign of the essential importance of L-carnitine for energy production and for the optimal function of membranes and cell metabolism. L-carnitine fulfills various tasks within the dynamic structure of the immune system:

• It is essential for the immune system to utilize fatty acids for energy. As L-carnitine transports long-chain fatty acids into the mitochondria, it can certainly be described as the "motor" of the immune system.
• In addition, L-carnitine protects the cell membranes from the damaging effects of activated fatty acids. Damaged membranes jeopardize the osmotic balance, increase the energy requirement and reduce the synthesis performance of the cells.

L-carnitine as an immunostimulant

Test results confirm that L-carnitine acts as a natural immune stimulant. In the case of deficiency symptoms caused by stress or sporting activity, for example, this can be compensated for with 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, so that the system is not overloaded. L-carnitine is therefore also used successfully in cases where other (herbal) immunostimulants are contraindicated, such as acute infections like sepsis, 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. For example, a study by Cerretelli and Marconi in 1990 showed that the intake of L-carnitine increases the overall concentration level in muscle cells and that study subjects covered longer walking distances on average. It can therefore 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 therefore help to reduce the risk of heart attacks. The broad therapeutic spectrum shows the nutritional significance of L-carnitine. The daily requirement for L-carnitine is between 200 and 1200 mg, depending on physical exertion.

Performance enhancement through L-carnitine

L-carnitine critics often focus on the lack of studies on the effectiveness of the vitamin. In fact, there are numerous independent studies. The studies prove that L-carnitine measurably improves physical performance and regeneration and boosts both cardiac output and metabolism. In over 40 studies, performance-enhancing effects were observed through the administration of L-carnitine. The latest study on performance enhancement through 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 regeneration and increased 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 of a physiological order of magnitude. Today, L-carnitine is a standard product in sports nutrition. It is not only the performance of athletes that can be positively influenced by L-carnitine. L-carnitine has also been shown to bring about a measurable increase in 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 is 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. L-carnitine also facilitates oxygen uptake during physical exertion. A sufficient supply of L-carnitine ensures that the muscles and cardiovascular system do not tire so quickly. The immune system is also strengthened, the defense cells are more active and more aggressive.

Who can benefit?

Generally speaking, anyone who is exposed to particular stress can benefit from L-carnitine. This includes people who suffer from muscle weakness or poor concentration as well as athletes whose muscles are exposed to constant 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, which 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 - cheer up with L-carnitine

Scientific studies have shown that men are more careless with their bodies than women. The male body therefore already suffers enough and deserves significantly more care and attention if it is to remain healthy and efficient and "stand its ground". However, if it is neglected, it takes revenge by becoming exhausted and listless. What makes tired men perk up? Milk alone is rarely enough to revive tired spirits. L-carnitine, which supplies the body with new energy, is a better remedy.

On average, men in the western world die seven years earlier than women. This is no coincidence: the stronger sex is much more careless with their bodies. 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 all kinds of illnesses. Fatigue, tiredness, listlessness: almost every man suffers from this. Yet men can easily do something for their own health: A daily intake of 1-3 grams of pure L-carnitine can help to boost the body's functions 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 physical exertion. The muscles, immune system and 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 of L-carnitine before exercise is enough to increase performance and endurance. The same applies to the heart and immune system, where the immune cells are strengthened. So men can be helped: Supplementing 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 is dependent 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 other micronutrient impairs L-carnitine synthesis, a vitamin C deficiency makes itself felt most quickly. The body's own carnitine synthesis covers around 10 % of the total L-carnitine requirement.

As the ability to synthesize L-carnitine is only fully developed from the age of 15, care must be taken to ensure that children in particular eat a diet rich in carnitine. Due to its involvement in fat metabolism, L-carnitine is mainly contained in muscle meat. This applies not only to L-carnitine sources from food, but also to the human organism. These figures underline how important L-carnitine is for muscle performance. The body's own synthesis of L-carnitine is not able to adapt to an increased demand. It tends to proceed slowly and is dependent on a number of other substances. If an increased need 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 a significant contribution to the body's energy production, is involved in detoxification processes and takes over the removal of activated fatty acids as part of ?-oxidation, there are various causes of an insufficient supply of L-carnitine.

• Reduced biosynthesis capacity
• reduced absorption in the intestine
• Reduced L-carnitine transport through the cell membrane
• increased excretion by the kidneys
• Increased requirement (during physical exertion or extraordinary stress)

Primary, secondary and functional L-carnitine deficiency

A distinction is made between primary and secondary L-carnitine deficiency. The term primary deficiency covers congenital or inherited disorders, which in turn are classified as myopathic or systemic forms.

Primary deficiency - myopathic form

Disorders of the myopathic form primarily affect the muscles. From a clinical point of view, the main symptom is usually 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, in addition to muscle weakness, myocardiopathy, encephalopathy (non-inflammatory diseases of the brain), hyperammonemia (increased ammonia concentration in the blood) and other disorders can be detected. 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 only 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 illness or drug treatment. A functional L-carnitine deficiency is characterized by an insufficient availability of free L-carnitine and leads to reduced performance, the main causes of a secondary L-carnitine deficiency being

• vegetarian lifestyle: Very little or no L-carnitine is found in plant-based products. Vegetarians therefore only consume 10-20% of the amount contained in a normal mixed diet.
• Age: Over the years, the body's own L-carnitine biosynthesis slows down. Current studies suggest that the free radicals produced during oxidation damage the mitochondrial system and thus accelerate the ageing process.
• Impaired absorption: L-carnitine is absorbed in the small intestine. In children suffering from coeliac disease (digestive insufficiency due to gliadin intolerance), greatly reduced L-carnitine levels can therefore be detected.
• Renal loss and dialysis: Chronic renal insufficiency leads to 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 surgery and in malignant diseases. Dialysis leads to greatly increased L-carnitine losses of up to 85% of the plasma content.
• Pregnancy: Of course, we are not talking about a disorder in this context, but carnitine levels can also be reduced by up to 50 % during pregnancy.
• Fasting and parenteral nutrition: In these special cases, the supply of L-carnitine via food is interrupted. In the case of tube feeding, however, L-carnitine can be added to the preparations.
• Oxygen deficiency: Oxygen deficiency, regardless of whether it is due to a reduced supply, e.g. due to vasoconstriction, or due to a sharp increase in oxygen demand as a result of intense physical activity (e.g. sport), leads to a reduction in the availability of free L-carnitine.

Getting to grips with spring fatigue

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

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

Studies carried out by Gross, Jewell and Bradley on seven animal species - including dogs, cats and fish - showed that the administration of L-carnitine reduces the body fat percentage and increases lean muscle mass. The scientists Ahmad, Spagnoli and Wohlers also proved that the muscle-building and muscle-maintaining effect of L-carnitine also applies 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, the fat is burned in the mitochondria and energy is released. L-carnitine therefore supports the reduction of body fat.

The daily requirement for L-carnitine is between 200 and 1200 milligrams, depending on physical exertion. In spring, not only figure-conscious people should make sure they take sufficient L-carnitine supplements. People who are plagued by spring fatigue in particular can use L-carnitine to counteract premature fatigue of the muscles and cardiovascular system. Foods such as crab or mutton provide natural L-carnitine. In concentrated form, the nutrient is available in the form of bars, tablets, capsules, chewing gum or probiotic drinks. Combined with outdoor exercise, it's a sure-fire way to feel better - and summer can come.

L-carnitine has a positive effect on fertility

High environmental pollution, stress, poor diet - there are many reasons for involuntary childlessness. One of the main causes is the steady decline in sperm quality in men. A lack of essential nutrients such as L-carnitine can often be observed in this context.

A growing percentage of couples remain unintentionally childless.

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

L-carnitine in the human body

Human organs such as muscles and the heart contain L-carnitine. The body produces some of the nutrient itself, but most of it is obtained from food (meat and dairy products are particularly rich in L-carnitine). Sperm are the most L-carnitine-rich cells in the male body, containing around 2000 times as much L-carnitine as the blood. In the form of acetyl-L-carnitine, the nutrient serves as a source of energy for the sperm on their way to the egg cell.

L-carnitine during pregnancy

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

Possibilities and limitations of L-carnitine

Studies have shown that L-carnitine has a positive influence on male fertility, as the administration of 3 g of L-carnitine per day results in a significant increase in sperm count, quality and motility after three to four months. However, infertility is a disease that must be treated by a doctor. L-carnitine is not a drug and is therefore not recommended for treatment. However, it has been proven that the reproductive capacity of people with a balanced diet is at its highest - therefore supplementation with L-carnitine is recommended in the event of a deficiency.

L-carnitine is power for the weak heart L-carnitine ensures a better supply to hearts with poor circulation

People with poor blood flow to the heart can reduce the risk of secondary diseases such as chronic cardiac insufficiency, angina pectoris or a heart attack by taking L-carnitine. Due to these disorders, an 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. Various studies have shown that an additional intake of one to two grams of L-carnitine per day is effective in improving the energy situation and performance of the heart (1,2,3).

This improvement can be explained by the function of L-carnitine to transport free fatty acids, which are 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. L-carnitine also 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 is less likely to become ill and is more efficient. Healthy people produce sufficient amounts of L-carnitine 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.

Requirements in sport

I have read many reports that an 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, as the carnitine concentration in the muscle itself does not change.

L-carnitine is broken down in the liver and transported from there to other body tissues that use fatty acids as a primary fuel source, for example to the skeletal muscles and the heart muscles. Once there, carnitine first removes the fat from the tissues and converts it into fuel. It then removes the troublesome by-products of fat metabolism from the mitochondrial matrix to prevent these substances from accumulating and forming new fats.

None of this would be the case with a carnitine deficiency. This does not mean that a carnitine deficiency will cause you to gain fat effectively, but the metabolism will slow down rapidly and so will fat burning. This can also be the case with healthy people, e.g. in very stressful 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. This is why it is so important to supplement carnitine so that it is always available in sufficient quantities and never get into such a situation.

Nobody has claimed that carnitine is the miracle cure for fat deposits, but you should bear in mind that high amounts of carnitine 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, strength training, dieting or anabolic steroids etc., as long as carnitine cannot fully develop 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 the chance to defend itself against the 30 billion fat cells by specifically upgrading your carnitine-dependent fat-burning matrix through regular and intelligent carnitine supplementation. According to recent studies, 1-4g of carnitine per day supports the effective functioning of this shuttle system and reduces the amount of blood triglycerides. The production of fat from dietary calories is called lipogenesis. Carnitine also has numerous other benefits and is therefore indispensable for us athletes:

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

L-carnitine and ketosis

Advocates of ketogenic (low-carb) diets claim that if there are not enough carbohydrates available to fuel the body, it will fall back on other sources of energy, namely stored body fat. However, if such diets are not strictly monitored, especially in diabetics, the released ketones can lead to hyperacidity of the blood and thus to excessive excretion of important electrolytes. This situation can get out of hand and become life-threatening if not monitored closely. It is now known that carnitine, with its fat-burning properties, prevents the accumulation of ketones in the body. Anyone following the Aktis diet or an abdere low-carb diet will therefore generally benefit from carnitine supplementation.

L-carnitine, better regeneration and better muscle contractions

Carnitine is not only responsible for transporting long-chain fatty acids into the mitochondria. Bodybuilders value 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 a placebo and once under the influence of carnitine. The difference in muscle damage was unmistakable: 16 to 23 percent (carnitine) compared to 29 to 39 percent (placebo).

Dosage

My recommendation is to take 2-4g of carnitine per day on an empty stomach. This amount should be divided into two to three doses. I hope 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 when injected after medical clearance. L-carnitine can cause some side effects such as nausea, vomiting, stomach upset, heartburn, diarrhea and seizures. It can also cause a fishy odor of urine, breath and sweat. L-carnitine may be safe and safe for children when taken for an appropriate, short-term period.

Precautions and warnings:

Pregnancy and breastfeeding: 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. It may be safe for breastfeeding women to take L-carnitine in reasonable amounts. Small amounts of L-carnitine have been administered to infants in breast milk or infant formula with no reported side effects.

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

Interactions with medications:

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

Acenocoumarol

Acenocoumarol is used to slow down blood clotting. L-carnitine could increase the effect of acenocoumarol. Increasing the effect of acenocoumarol could slow down blood clotting too much. The acenocoumarol dosage may need to be adjusted if you are taking L-carnitine.

Thyroid hormones

L-carnitine appears 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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