L-Carnitine caution!

It is evident that strict vegetarians consume diets low in
carnitine. In addition such diets are often low in lysine and
methionine, which are need for carnitine biosynthesis
(manufacture in the body). Also, lysine is sensitive to heat.
Frying, broiling, baking and toasting are known to kill this
amino acid, and many lysine-rich foods, eg. meats, are cooked at
high temperatures thus the dietary intake of lysine may be
marginal even those eating a balanced diet. Consequently such
individuals are likely to be deficient in carnitine. Also note
that vitamin C is also required for the biosynthesis of
carnitine, and of all the nutrient co-factors studied to date,
ascorbic acid levels exert the most marked effects on the rate
of carnitine biosynthesis. Carnitine is the third natural
component of body cells, plus vitamin C and Coenzyme Q10,
that serves to complete the triad of energy production