Spring 2002 Issue — Satisfying the Challenged Manufacturer and Knowledgeable Consumer with L-Carnitine

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Manufacturers of nutraceuticals are increasingly challenged to meet the demands of the savvy consumer. Nowadays, the average consumer expects manufacturers to develop products that are effective in helping with current health, in reducing the risk of developing diseases, and in improving long-term health. Consumers demand safe products. And in this "age of choice", consumers want to be able to get their nutraceuticals in different delivery forms, be it from tablets, capsules and beverages to sports bars, chewing gums, and more traditional foods. Although many substances are discussed as nutraceuticals, there is clearly one product that stands alone in terms of effectiveness, safety and suitability for processing, thereby satisfying both the consumer and the manufacturer alike. That product is L-Carnitine.

What is L-Carnitine?

L-Carnitine is an amino acid-like and vitamin-like nutrient which is found naturally in the human body. The highest concentrations occur in the heart and skeletal muscle. While L-Carnitine can be synthesized in the body, for the most part, the daily requirement of L-Carnitine is met by food intake. Foods from animal sources are high in L-Carnitine, fruits and vegetables contain minimal amounts. This has obvious implications for vegetarians and the manufacturers of vegetarian-targeted products.

The primary role of L-Carnitine within the body is to shuttle long-chain fatty acids into the mitochondria, the "furnace of the cell". Within the "furnace" the fatty acids are broken down or burned and energy is produced. Thus, L-Carnitine is essential for the production of energy from fat! This observation has prompted extensive clinical research into the potential applications of L-Carnitine. Consequently, nowadays, owing to mounting positive scientific evidence, L-Carnitine or Carnitine Magnesium Citrate (U.S. Patent 5,071,874 and other international patents) are key or sole components of nutrition products targeted for cardiovascular health, sports performance and weight management. Furthermore, since the early 1980's, L-Carnitine has been routinely added to infant formulas, especially those that are soy-based.

Benefits of L-Carnitine Supplementation Support for Cardiovascular Wellness

Most people don't realize that the heart obtains 70% of its energy from fat breakdown. 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 production. Therefore, it is not surprising that clinical data indicates that dietary L-Carnitine can positively support healthy heart muscle, can significantly increase heart muscle viability and is beneficial in supporting a healthy heartbeat. For example, it was found that in individuals diagnosed as having a heart attack, dietary L-Carnitine (4 g/day for 12 months) in conjunction with pharmacological treatment, led to decreased incidence of arrhythmias and angina. But most importantly, L-Carnitine supplements people showed a remarkable reduction in mortality of 1.2% as compared to 12.5% in the control group.

Other clinical research data indicate that L-Carnitine supplementation (2 g/day for 6 months) in addition to routine medication is helpful in maintaining healthy cholesterol and triglyceride levels.

New Research on L-Carnitine and Recovery from Exercise

Traditionally L-Carnitine us used among physically active people to help improve their performance, while simultaneously delaying the onset of fatigue. However, the latest breakthrough clinical research points to another important role for L-Carnitine: enhancing recover from strenuous exercise. This latest research provides physically active and even inactive people with an additional reason to supplement with this nutraceutical.

"Weekend warriors" or recreational athletes typically experience soreness and stiffness in exercised muscles following an extended lay-off from exercise. A temporary soreness may persist for several hours whereas a residual soreness or delayed onset muscle soreness (DOMS) may appear later and last for 3 or 4 days after the unaccustomed exercise. On a temporary basis, DOMS can adversely affect muscular performance, both from voluntary reduction of effort and from inherent loss of muscle capacity. Nearly everyone has experienced DOMS at some time promising huge potential for a nutraceutical that can help battling this problem.

The most recent clinical study which was published in the American Journal of Physiology, Endocrinology and Metabolism showed that L-Carnitine L-Tartrate supplementation significantly helps "weekend warriors" during recovery from high intensity exercise. The study was conducted by a team of scientists led by Professor William Kraemer and Dr Jeff Volek at Ball State University in Indiana. The study was funded by Lonza, the largest manufacturer of L-Carnitine in the world. Due to a patented production process, Lonza is the only L-Carnitine manufacturer able to supply 100% pure L-Carnitine without any harmful D-Carnitine in their product line, hence the brand name and sign of quality assurance L-CARNIPURE®.

Using a balanced, placebo, cross-over design, ten healthy active volunteers (mean age 23.7 years) acted as their own control taking either a placebo or an L-CARNIPURE® L-Carnitine L-Tartrate supplement (equivalent to 2 g L-Carnitine/day) for 3 weeks prior to the performance of a controlled exercise session. Various indicators of recovery were measured in the first 3 hours after the exercise and then again at 24, 48, 72 and 96 hours after the exercise session. The exciting results of the study indicated that supplementing with L-Carnitine L-Tartrate prior to high intensity exercise is significantly effective in assisting recovery. More specifically, supplementation allows for decreased production of free radicals, less tissue damage, reduced muscle soreness and better utilization of fat as an energy source during recovery.

Another recently published study also looked at the effect of L-Carnitine L-Tartrate supplementation on recovery from intense exercise. This study differed from the DOMS study above in that it focused on the effect of supplementation on accelerating short-term recovery after strenuous exercise. This Lonza sponsored study was performed under the guidance of Professor Paul Walter at the University of Basel in Switzerland.

In this double blind, placebo-controlled, cross-over study, twelve healthy men and women (mean age 25.7 years, 6 untrained and 6 trained) volunteered and acted as their own control taking either a placebo or an L-CARNIPURE® L-Carnitine L-Tartrate supplement (equivalent to 2 g L-Carnitine/day) for 5 days. The power output of each individual was initially established and then each subject performed a strenuous 15 minute bike ride. Recovery was subsequently measured in terms of power output that could be generated following the bike ride. The mean power output measured during the 25 minutes following strenuous exercise was improved significantly by 11-14% following supplementation with L-Carnitine L-Tartrate for 5 days, thereby indicating that L-Carnitine also has a role to play in enhancing short-term recovery.

L-Carnitine, a Natural Approach for Weight Management

Most people may be familiar with L-Carnitine as a weight management supplement. Again there is clinical research to indicate that L-Carnitine supplements are useful in promoting weight loss, when used as part of an overall weight management program.

The most recent study performed in 100 obese people provided convincing data about the beneficial effects of L-Carnitine in conjunction with dieting and moderate exercise. Obese people had a 25% greater loss in body weight if they supplemented with L-Carnitine and their Body Mass Index (BMI = body weight/(height)²) dropped by 1.5, indicating that they were coming closer to their ideal body weight. Total cholesterol, low density lipoprotein, blood sugar and blood pressure were significantly lower in the L-Carnitine group as compared to control. The authors concluded that supplementary L-Carnitine is necessary to guarantee optimal fat oxidation and consequently body weight reduction.

It is important to bear in mind that the dietary supplement L-Carnitine is not recommended to treat obesity. This is a disease that requires intervention by a health professional. However, clinical research indicates that supplementary L-Carnitine supplementation may promote a healthier body weight. It therefore can be an important part of a healthy weight management program for individuals concerned about their weight.

Safety Issues

L-Carnitine is possibly one of the safest nutraceuticals in the marketplace today. A panel of experts have concluded that L-Carnitine is Generally Recognized as Safe (GRAS), i.e., L-Carnitine has self-affirmation GRAS status. It is worthwhile noting that Carnitine can exist in the isomeric form L-Carnitine and D-Carnitine. Only L-Carnitine is the naturally occurring and effective form. In fact, D-Carnitine is harmful and the FDA have banned the import of D and D,L-Carnitine is the US since 1983. However, depending upon the manufacturing process used to produce L-Carnitine, some D-Carnitine may still be found in L-Carnitine products. Due to a unique patented manufacturing process. Lonza is the only manufacturer of L-Carnitine that guarantees the absence of D-Carnitine from all products, hence the brand name L-CARNIPURE®.

Clinical studies supporting the safety of L-Carnitine include those conducted with Lonza's L-CARNIPURE® L-Carnitine L-Tartrate. In a double blind, placebo-controlled crossover study, ten healthy male volunteers consumed 3g CARNIPURE® L-Carnitine L-Tartrate (equivalent to 2 g L-Carnitine/day) or a cellulose placebo capsule in two doses per day with meals for 21 days. A one week washout occurred between crossover treatment periods. Daily supplementation with 3 g CARNIPURE® L-Carnitine L-Tartrate resulted in no significant changes in any measured parameter of hematology, or liver and kidney function, compared to 21 days of daily supplementation with placebo. Furthermore, all measured parameters were within the normal range following CARNIPURE® L-Carnitine L-Tartrate and placebo treatments. The study was recently published in the Journal of Strength and Conditioning Research.

Manufacturing with L-Carnitine

The physical properties of L-Carnitine and salts of L-Carnitine, such as L-Carnitine L-Tartrate and L-Carnitine Magnesium Citrate, make these products manufacturer-friendly. They are bright white, heat stable and highly water soluble. One drawback associated with L-Carnitine itself is that it is hygroscopic, i.e., it actively absorbs moisture. While this is not an issue when making beverages, it may lead to difficulties when making tablets and capsules. Stable, non-hygroscopic salts of L-Carnitine were developed by Lonza to overcome the hygroscopicity problem. Among all salt forms currently commercially available, L-Carnitine L-Tartrate contains the highest concentration of L-Carnitine (68%). In addition to ease of handling, L-Carnitine L-Tartrate has a pleasant, citrus-like flavour.

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