What is L-Carnitine?

L-Carnitine, a natural nutrient also used to be known as vitamin BT, is an essential nutrition in our body that transports long chain fatty acids across the mitochondrial membrane to turn fat into energy;

Fatty Acid Oxidation
Though fatty acids are one of the primary energy sources for the body, they cannot produce energy until they are broken down in mitochondria (the 'furnace' of the cell) through a process called, ß-oxidation. This is where L-Carnitine comes in to play an essential role to complete the process since fatty acids alone cannot penetrate the inner mitochondrial membrane and enter the mitochondria for subsequent fat breakdown and energy production.

Free Co-Enzyme A (CoA) Buffer
Additionally, L-Carnitine has been shown to buffer the bound CoA to free CoA ratio and removes toxic concentrations of acyl-CoA thereby helping to ensure that energy production can continue.

Detoxification
Another important function of L-Carnitine is the ability to shuttle short chain organic acids from inside the mitochondria to the cytosol.

Where can we find L-Carnitine?

<In Our Body>
		A small amount of L-Carnitine is naturally produced on a daily basis within the human body and average adults store about 20 grams of L-Carnitine in their bodies, primarily in skeletal muscle, in the liver, and in the heart. L-Carnitine is not metabolized or degraded, but excreted in the urine, mostly in the form of L-Carnitine esters. Therefore, lost L-Carnitine has to be replenished by biosynthesis, by the consumption of foods of animal origin or by consumption of dietary supplements.
<In Food>
		L-Carnitine is found to varying extents in foods of animal origin while fruit and vegetables contain very little, if any, L-Carnitine. For instance, 100g of uncooked lamb contains 190mg of L-Carnitine while 100g of uncooked mushroom contains only 2.6mg. And 100g of uncooked beef contains 143mg L-Carnitine while 100g of uncooked rice contains only 0.3mg.

Why do we need L-Carnitine dietary supplement?

The major sites for L-Carnitine biosynthesis are the liver and kidney. Biosynthesis requires two essential amino acids, lysine and methionine, as well as vitamin C, iron, vitamin B6, niacin and involves a series of enzymatically catalyzed reactions. The requirement for all these essential nutrients implies that malnutrition has a highly negative impact on L-Carnitine biosynthesis.

L-Carnitine biosynthesis yields approximately 20 mg L-Carnitine per day (representing approximately 10% of the daily requirement) if all co-factors are readily available in the body. A well balanced diet can supply an additional 100-300 mg of L-Carnitine to the body each day. However, with many of us lacking in these co-factors to begin with or missing a well balanced diet more often than not, consuming L-Carnitine in a dietary supplement will ensure that we meet the daily requirement and maintain an optimum health. For specific health benefits, please refer to the studies below.

Why Carnisol^®?

Carnisol^® is the only L-Carnitine supplement available in a soft gel, therefore, it provides the benefits of a natural L-Carnitine with maximum absorption.

The main ingredient of Carnisol^® derives from L-Carnipure^® - L-Carnitine L-tartrate (a free flowing L-Carnitine salt containing L-Carnitine (68%) and natural GRAS L-tartaric acid (32%)), which was developed by Lonza - the only supplier who can guarantee 100% pure, natural L-Carnitine - totally free from toxic D-Carnitine. In fact, L-Carnitine used in Carnisol^® fulfills all relevant food and pharma standards and is kosher certified without using GMO's or materials of animal origin.

Clinical trials indicate that taking L-Carnitine regularly prior to exercise promotes increased energy and endurance without accelerating the heart rate.* Carnisol^® also promotes efficient post-exercise recovery, supports healthy cardiovascular function, male fertility, healthy aging, and facilitates fat breakdown - without a loss of lean muscle tissue.*

Introduction

L-Carnitine has been used by sports enthusiasts since the early 1980’s. The physiological function of L-Carnitine in facilitating the production of energy from fat is crucial during exercise (especially endurance exercise) because fat is one of the main fuels used to provide energy for physical activity. Clinical research indicates that supplemental L-Carnitine is beneficial in terms of optimizing performance, delaying the onset of fatigue and enhancing the recovery process. Scientists have also observed that exercise actually leads to increased losses of L-Carnitine in urine¹. This loss may be followed by a decrease of L-Carnitine in the active muscles which may not always be rapidly replenished by the normal processes, thus L-Carnitine supplementation may be warranted². Supplemental L-Carnitine is also helpful in assuring that the heart receives the extra energy it needs during exercise. The positive effects of L-Carnitine are not restricted to endurance athletes; “weekend warriors” can also benefit.

L-Carnitine and Exercise Performance

A number of research reports indicate that L-Carnitine may be of value in enhancing exercise performance.

• In 1997, researchers reported that marathon runners who supplemented with L-Carnitine (2g/day for 6 weeks) increased their peak treadmill running speed by an average of 5.7%³. Exercise physiologists have traditionally used VO2max as the yardstick to measure the capacity for endurance exercise. In simple terms,VO2max is one of the most important determinants of one’s ability to sustain high-intensity exercise for longer than 4-5 minutes. VO2max values are higher in people who are trained as compared to sedentary individuals⁴. Clinical research indicates that L-Carnitine can help to increase VO2max in both endurance athletes and “weekend warriors”.
• When competitive long distance walkers supplemented with L-Carnitine (4g/day for 2 weeks), a 6% increase in VO2max was observed⁵. According to experts, even a 5% increase in VO2max can transform an “average” into a “top” competitive athlete²!
• Training for one month led to an increase in VO2max in untrained cyclists.When training was combined with L-Carnitine supplementation (50mg/kg body weight/day) the increase in VO2max (11%) became significant⁶. The bottom line ­ L-Carnitine supplements may be of value when striving for improved exercise performance!

L-Carnitine and Exercise-Induced Fatigue

Research suggests that L-Carnitine supplementation may help with delaying the onset of fatigue during exercise. It doesn’t take a rocket scientist to realize that fatigue during exercise is undesirable as it ultimately compromises performance. Two key causes of fatigue during exercise are lactic acid accumulation and glycogen depletion.

L-Carnitine and Lactic Acid
During exercise, a substance known as lactic acid accumulates in the muscles and can eventually diffuse into the bloodstream. This is significant because fatigue is associated with the accumulation of lactic acid in the muscles and blood. The amount of lactic acid produced depends upon the exercise intensity and duration, as well as the person’s level of fitness. For example, exercise involving high intensity legwork, such as running⁷ or prolonged high intensity exercise such as a 20 km racewalk can lead to the accumulation of lactic acid and fatigue. Obviously a reduction in lactic acid accumulation during exercise is desirable, since this will delay the onset of fatigue.

In this respect, various researchers have found promising results with L-Carnitine.

• In a double-blind crossover trial, ten moderately trained volunteers took 2g of L-Carnitine or placebo one hour prior to an intense cycling exercise. The rise in blood lactate was significantly reduced by L-Carnitine and was accompanied by an astounding 22.5% increase in working capacity⁸.
• In a similar study, researchers reported significantly decreased blood lactic acid levels, a significantly increased work output and a 7% increase in VO2max. They concluded that under the conditions of their experiment, L-Carnitine favors aerobic processes thereby resulting in a more efficient performance⁹.
• In a double blind placebo-controlled study involving elite rowers, L-Carnitine administration (3g/day for 3 weeks) resulted in significantly decreased lactic acid levels and significant increases in VO2max and strength index¹⁰.

L-Carnitine and Glycogen Depletion
Fat and carbohydrate are the two main fuels used to provide the energy required for exercise. Fat sources comprise of fatty acids derived from fat stores in muscle and adipose tissue while carbohydrate sources consist of blood glucose and muscle glycogen (many glucose molecules linked together). Depletion of muscle glycogen results in fatigue⁷. Intense activities that demand a high output of energy in a short time frame, such as sprinting, quickly deplete glycogen stores¹¹. During prolonged exercise, e.g. a marathon, muscle glycogen stores can also become depleted⁴. If the use of fat as an energy source can be increased during exercise, this may spare muscle glycogen, thereby delaying the onset of fatigue.

Again, there is research to indicate that L-Carnitine may be beneficial in this respect.

• In endurance trained athletes, L-Carnitine supplementation (2g/day for 28 days) led to a significant reduction in Respiratory Quotient (RQ) during a 45 minute cycling exercise, as compared to placebo. This decrease in RQ indicates increased utilization of fat and a possible carbohydrate (glycogen) sparing effect and ultimately, should be associated with improved performance¹².
• Similarly, in marathon runners who took L-Carnitine (2g/day for 6 weeks) a decline in the Respiratory Exchange Ratio was observed, again indicating a greater dependence upon fat utilization during endurance exercise³.

In summary, there is data to indicate that L-Carnitine is helpful in delaying the onset of fatigue.
And remember: minimizing fatigue is one step toward maximizing performance¹¹.

L-Carnitine and Recovery

We all know the feeling ­ enthusiastically you set out for a hike in hilly countryside or your first step aerobics class and the next day your legs are so tender and stiff that you can barely hobble! What you are actually suffering from is called Delayed Onset Muscle Soreness (DOMS).

DOMS is the sensation of discomfort or pain in the skeletal muscles that occurs following unaccustomed muscle exertion and appears to be due to tissue injury caused by excessive mechanical forces exerted upon muscle and connective tissue. The muscle soreness normally increases in the first 24 hours after exercise, peaks in 1-3 days and then subsides¹⁴. According to clinical research, L-Carnitine may be of assistance in alleviating the pain and tenderness following exercise.

In untrained subjects, L-Carnitine supplementation (3g/day for 3 weeks) as compared to placebo, significantly reduced muscle pain (Figure 2) and tenderness after exercise and decreased muscle damage15.

Conclusion

Not only is L-Carnitine an important supplement for the heart, it also holds promise in terms of exercise performance, fatigue and recovery for both the well-trained athlete, who can possibly be at risk of L-Carnitine deficiency due to increased urinary losses and the untrained “weekend warrior”. In fact, it may be suggested that L-Carnitine has a “training-like” effect in “weekend warriors” as it can help to enhance performance, delay fatigue and even alleviate a painful recovery. So, whether or not you are in training for the Olympics, L-Carnitine has something for everyone!

Introduction

The heart requires an abundant supply of energy to achieve its working capacity. So, where does this energy come from? Well, mostly from the burning of fatty acids - in fact, the heart derives around 70% of its energy from fat breakdown². Since L-Carnitine is central to the formation of energy from fat, the heart is consequently dependent upon L-Carnitine for most of its energy production³. It is well known that regular exercise is vital for maintaining a healthy heart. While many sports enthusiasts and weekend warriors take L-Carnitine for enhanced performance and more rapid recovery, supplementing with L-Carnitine when exercising has the additional benefit of helping to support healthy heart function. Exercise, while ultimately beneficial for the heart, increases the workload of this vital organ and consequently the heart’s energy requirement increases. Supplemental L-Carnitine is helpful in assuring that the heart receives the extra energy it needs during exercise.

Benefits of L-Carnitine on Cardiovascular Health (based on science)

Cardiovascular disease is the leading cause of death in the industrialized world and according to the American Heart Association, in 1995 almost 14 million people in the US had some form of heart disease, be it a heart attack, angina or other heart condition. From a review of scientific literature, it is clear that L-Carnitine’s benefits are not confined solely to healthy heart function ­ extensive clinical data indicates that oral L-Carnitine supplementation is beneficial in maintaining healthy cholesterol levels and, can be used even after cardiovascular conditions develop.

Clinical data indicates that L-Carnitine supplementation can support healthy heart muscle4 and can significantly increase heart muscle viability⁵.
“Heart attack” is a term with which we are all familiar. In essence, a heart attack (myocardial infarction) occurs when the blood supply to the heart muscle is either severely reduced or completely cut off. This causes damage and death to the heart muscle cells due to lack of oxygen and ultimately may be fatal to the individual.

Sampling of substantiation in support of dietary supplement claims: Clinical data has shown that in addition to routine pharmacological treatment, L-Carnitine supplementation (2g/day for 28 days) results in a significant reduction in average infarct size in individuals who have experienced a recent acute heart attack. Thus, L-Carnitine can help to protect against heart damage following a heart attack⁴. Furthermore, L-Carnitine supplementation (2.97g/day for 8 weeks) can significantly increase heart muscle viability in individuals who have suffered a heart attack⁵.

L-Carnitine supplementation is beneficial in supporting a healthy heartbeat^4,6.
Angina is the temporary chest pain which occurs when the heart muscle isn’t receiving enough oxygen, while arrhythmia is the scientific term for irregular heartbeat. In 1995, it was estimated that over 7 million people in the US suffer from angina.

Sampling of substantiation in support of dietary supplement claims: In the first study described above, L-Carnitine supplementation was shown to significantly reduce incidence of angina and arrhythmias (Figure 3). Additionally, L-Carnitine was associated with a decreased need for anti-angina and anti-arrhythmic medication4.

In terms of cardiovascular support, perhaps one of the most astounding results of L-Carnitine supplementation was reported in 1992.

It was found that in individuals diagnosed as having a recent heart attack, L-Carnitine supplementation, in addition to the pharmacological treatment generally used, led to decreased incidence of arrhythmias and angina and, most importantly, caused a remarkable and significant reduction in mortality ­ 1.2% in the L-Carnitine group as compared to 12.5% in the control group6 (Figure 4).

L-Carnitine supplementation increases exercise tolerance and supports healthy heart function^7-10.
In people with stable effort-induced angina, the capacity for physical activity is unfortunately limited due to the onset of chest pain upon exercise.

Sampling of substantiation in support of dietary supplement claims: In stable angina, L-Carnitine (2g/day for 6 months), in addition to current medication, has been shown to significantly enhance exercise tolerance, improve cardiac function and reduce consumption of cardioactive drugs⁷.

Benefits of L-Carnitine on Maintaining Healthy Cholesterol Levels (based on science)

Clinical data indicates that L-Carnitine supplementation is helpful in maintaining healthy blood cholesterol and triglyceride levels⁷.
As we all know only too well, a high level of cholesterol in the blood is a major risk factor for the development of heart disease. Here again, clinical research reports that L-Carnitine supplementation may be beneficial.

Sampling of substantiation in support of dietary supplement claims: In a randomized trial involving individuals with stable angina, supplemental L-Carnitine, in addition to routine medication, was shown to cause a significant decrease in blood cholesterol and triglyceride levels7 (Figure 5).

L-Carnitine’s Mechanism of Action in Support of Dietary Supplement Claims

Since oxygen is needed for fat breakdown, in conditions where the heart muscle cells are not receiving enough oxygen, e.g. heart attack and angina, fat breakdown and energy production in the heart muscle is reduced. Furthermore, there is a decrease in the free L-Carnitine concentration in the cardiac cells. These events ultimately lead to impairment of the mechanical functioning of the heart. Scientists agree that L-Carnitine supplementation helps by replenishing the lost L-Carnitine and by enhancing fat breakdown and energy production^14,15. In heart failure, there is also a deficiency of free L-Carnitine in the heart and it is thought that supplemental L-Carnitine helps by promoting energy production on the part of the heart muscle cell^12,13. In terms of its effects on cholesterol levels, L-Carnitine may act by simply enhancing fat breakdown.

Conclusion

It is clear ­ L-Carnitine has a well-documented part to play in supporting a healthy cardiovascular system. Everyone knows that “prevention is better than cure”. Consequently, by helping to support healthy heart function and by helping to maintain healthy cholesterol levels, L-Carnitine supplements may be a useful ally in the quest for cardiovascular health.

Introduction

Although philosophers and scientists have long been interested in the aging process, general interest in this fascinating and highly important topic was minimal before the 1960s. In recent decades, however, interest in aging has greatly accelerated. Early in the next century, there will be more Europeans over 60 years than under 201. According to the WHO, both the number and the proportion of older persons ­ defined as aged 60 and over ­ are growing in virtually all countries. Present worldwide trends are likely to continue unabated. Today, there are an estimated 580 million elderly people in the world, whereas by 2025, this figure is expected to rise to 1000 million. In the developed world, the very old (age 80+) is the fastest growing population group2.

What happens in the body when we get old?
Clinically, aging is the progressive accumulation of changes occurring in an organism which ultimately lead to death⁴. Numerous aging theories have been proposed. Although it is abundantly clear that our genes influence aging and longevity, exactly how this takes place on a chemical level is only partially understood⁵. Oxygen radicals are increasingly discussed as an important factor involved in the phenomenon of biological aging of all the tissues in the body⁶. The survival of an organism may depend on its ability to overcome the toxic effects of free radicals.

What are free radicals?
The body’s cells use oxygen in metabolic reactions. In this process, oxygen sometimes reacts with body compounds and produces highly unstable molecules known as free radicals. In addition to normal body processes, environmental factors such as radiation, pollution, tobacco smoke, and a high-fat diet generate free radicals. Free radicals can lead to widespread damage as they attack polyunsaturated fatty acids in cell membranes and alter functions of cell proteins and their DNA, creating mutations⁷.
The body contains a couple of lines of defense against free radical damage. The major antioxidative defense system in the body includes scavengers such as glutathione, vitamin C, vitamin E and antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase⁸.

L-Carnitine and Healthy Aging

According to Dr. Bruce Ames from the Berkeley and Children’s Hospital, California, USA, the mitochondria are the “weak link in aging”⁹.Their function decreases largely with age⁷. The mitochondrium, also referred to as the “furnace of the cell”, is the place of fatty acid and glucose oxidation [breakdown] and ultimate energy generation. In these processes, L-Carnitine plays a major role. It shuttles the long chain fatty acids through the inner mitochondrial membrane¹⁰. Furthermore, it supports the availability of free Coenzyme A. Accumulating acetyl moieties are transferred from Coenzyme A to L-Carnitine. Elderly people have a lower energy demand and eating habits change with age^2,11. For example, they usually consume less meat. At the same time, the dietary intake of both L-Carnitine and the nutrients required to make L-Carnitine is reduced. A decreased endogenous synthesis could also be shown by researchers¹². A decrease of L-Carnitine in various body compartments with age has often been described in literature^13,14.The resulting reduction in energy metabolism due to lower L-Carnitine levels can be restored by L-Carnitine supplementation. Two months of L-Carnitine L-Tartrate administration (2g/d) was shown to partly reverse age-related changes of oxidative metabolism in elderly females¹⁵.

L-Carnitine in the muscle
Skeletal muscles contain a high proportion of mitochondria, since they require a lot of energy during work. Thus it is no wonder that they constitute the main reservoir of L-Carnitine in the body and have an L-Carnitine concentration at least 200 times higher than blood plasma. Muscle mass and muscle strength tend to decrease with age²⁵. This can lead to a reduction in physical ability and may cause adverse metabolic effects. Analysis of muscle samples of healthy humans of different age showed a drastic reduction of L-Carnitine and acyl-L-Carnitine in the older subjects^26,27. Costell and Grisolia²⁸ discuss an alteration of the L-Carnitine carrier in the muscle cell membrane as reason for muscle L-Carnitine reduction with age. One month’s treatment with L-Carnitine in subjects aged from 70 to 92 was found to be associated with a significant increase in total muscle mass, compared with placebo. The total fat mass was reduced at the same time²⁴.

L-Carnitine and immune system
One of the most dramatic and consequence-bearing agerelated phenomena is the decline of the immune function with old age³⁴, which may predispose to several diseases commonly associated with increasing age³⁵. By stabilizing biomembranes against inflammatory agents, L-Carnitine abolishes the age-related increase in plasma membrane viscosity. It could be shown that L-Carnitine treatment can prevent the decrease in neutrophil chemotactic activity. Treatment with L-Carnitine was found to prevent the agerelated increase of superoxide production by neutrophils in old rats. This effect of L-Carnitine may be related to inhibition of protein kinase C activity. Protein kinase C is an enzyme involved in signalling processes. It is well known that L-Carnitine inhibits the age-related increase in protein kinase C-mediated response in human neutrophils. Overall, although more research is required, L-Carnitine supplementation may be supportive of healthy and general immune function.

Conclusion

With a two-fold increase in the world’s elderly predicted between 1998 and 2025, it is not surprising that the market for anti-aging foods and supplements will see increased levels of activity and opportunity for manufacturers. L-Carnitine can be regarded as the ideal nutrient for a long life, as it comprises all the benefits that seniors need to stay fit and healthy in both mind and body.