Supplementing Vegetarian Diets

In Europe, the average dietary L-Carnitine intake has decreased by about 20% over the last decade, mainly as a result of a decrease in beef intake.

The rising awareness and uptake of vegetarianism as a method of addressing health related food scares and animal cruelty issues, plus the fact that broadening ranges of vegetarian products are bringing the sector into the mainstream market, have resulted in the need to look at the vegetarians’ supply with certain nutrients. Although a meat-reduced or vegetarian diet can be a healthy choice and has various benefits, there are certain nutritional concerns associated with being a vegetarian. Dietary supplementation from non-animal based sources is required to meet nutritional guidelines.

Animal products, such as lamb, beef and pork, contain the highest amounts of dietary L-Carnitine. Lower levels of L-Carnitine are found in dairy products. In many plant foods, LCarnitine levels cannot even be detected. Strict vegetarians therefore have negligible sources for this nutrient. The typical non-vegetarian, Western diet is estimated to provide around 100-300 mg L-Carnitine per day. In Europe, however, the average dietary L-Carnitine intake has decreased by about 20% over the last decade, mainly as a result of a decrease in beef intake.

Reduced Carnitine Intake
Ovo-lacto-vegetarians are estimated to have an intake of about 10-40 mg L-Carnitine per day. With a strict vegetarian diet, the total amount of ingested L-Carnitine is further reduced and was found to be around 1-4 mg/day. The consequences of impaired L-Carnitine ingestion upon vegetarian health and nutrition have received relatively little or no attention to date in man. This is surprising, as the L-Carnitine requirements of the body are met almost exclusively from the consumption of meat, with limited de-novo synthesis. If intake of L-Carnitine is low, however, the body must almost entirely rely on the endogenous synthesis to meet the needs. A vegetarian diet is frequently low in some of the nutrients that are essential for L-Carnitine biosynthesis in the body, such as the amino acids lysine and methionine as well as iron.

Essential Nutrient
Noteworthy is that L-Carnitine is considered to be an essential nutrient for infants because, unlike adults, infants are unable to synthesise enough L-Carnitine in their bodies to meet their requirements. L-Carnitine is present in breast milk and for some years now, manufacturers of soy-based infant formula have been fortifying their products with L-Carnitine which would otherwise be devoid of this ‘conditionally essential’ nutrient.

Application Possibilities
In 1905, L-Carnitine was isolated for the first time from Liebig’s meat extract. At that time, Liebig’s meat extract was a popular ‘dietary supplement’ and often administered to patients during recovery from severe diseases. The time when L-Carnitine could only be found in red meat, however, is well behind us. These days, L-Carnitine can be found in functional beverages such as energy drinks, sports drinks, near waters, but also functional food and dietary supplements.

As the functional food and nutraceutical industry emerges from a specialised into a mainstream market, a key challenge for functional food manufacturers is to provide a product that not only delivers on performance but also on taste and texture. L-Carnipure L-Carnitine Crystalline and L-Carnitine L-Tartrate are manufacturer-friendly. Both products are bright white, heat stable, highly water soluble and form colourless solutions.

Differing Isomers
During classical chemical synthesis of Carnitine, both isomers are produced in even parts. Whereas L-Carnitine is the naturally occurring and biologically active form, present in nature and in our bodies, D-Carnitine does not exist in nature and is harmful to the human body. D-Carnitine competes with the L-isomer for the same uptake mechanisms and inhibits the utilisation of L-Carnitine. The L-Carnitine separation from the racemic mixture of synthetically produced DL-Carnitine is a very complex operation, therefore a new process had to be found which would only produce L-Carnitine.

Researchers at Lonza developed the L-Carnipure process, which makes use of a biotransformation step for stereo-selective introduction of the optical centre for the synthesis of pure L-Carnitine from an optically inactive precursor molecule.

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