SHORT COMMUNICATION
Correlation of Carnitine Levels to Methionine and Lysine Intake
M. KRAJČOVIČOVÁ-KUDLÁČKOVÁ, R. ŠIMONČIČ, A. BÉDEROVÁ,
K. BABINSKÁ, I. BÉDER1
Research Institute of Nutrition, Bratislava and 1Institute of
Physiology, Faculty of Medicine, Comenius University, Bratislava, Slovak
Republic
Received May 24, 1999
Accepted October 26, 1999
Summary
Plasma carnitine levels were measured in two alternative
nutrition groups – strict vegetarians (vegans) and lactoovovegetarians
(vegetarians consuming limited amounts of animal products such as milk products
and eggs). The results were compared to an average sample of probands on mixed
nutrition (omnivores). Carnitine levels were correlated with the intake of
essential amino acids, methionine and lysine (as substrates of its endogenous
synthesis), since the intake of carnitine in food is negligible in the
alternative nutrition groups (the highest carnitine content is in meat, lower is
in milk products, while fruit, cereals and vegetables contain low or no carnitine at all). An average carnitine level in vegans was significantly
reduced with hypocarnitinemia present in 52.9 % of probands. Similarly, the
intake of methionine and lysine was significantly lower in this group due to the
exclusive consumption of plant proteins with reduced content of these amino
acids. Carnitine level in lactoovovegetarians was also significantly reduced,
but the incidence of values below 30 m mol/l was
lower than in vegans representing 17.8 % vs. 3.3 % in omnivores. Intake of methionine and lysine was also significantly reduced in this group, but still
higher compared to vegans (73 % of protein intake covered by plant proteins).
Significant positive correlation of carnitine levels with methionine and lysine
intake in alternative nutrition groups indicates that a significant portion of carnitine requirement is covered by endogenous synthesis. Approximately two
thirds of carnitine requirement in omnivores comes from exogenous sources. The
results demonstrate the risks of alternative nutrition with respect to the
intake of essential amino acids, methionine and lysine, and with respect to the
intake and biosynthesis of carnitine.
Key words
Carnitine · Vegans · Lactoovovegetarians · Omnivores
Reprint requests
M. Kudláčková, PhD., Research Institute of Nutrition, Limbová 14, 833 37 Bratislava, Slovak Republic.
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