Last modified on 18 December 2014
[Technically carnitine refers to a mix of the D and L forms of carnitine, but I shall use the term carnitine interchangeably with L-carnitine, which is the 'active' form of carnitine in this respect.]
Carnitine is the carrier molecule that takes fuel in the form of acetate groups from the cell across mitochondrial membranes where it is needed to fuel energy production by Kreb's citric acid cycle and oxidative phosphorylation (Please see Fibromyalgia - possible causes and implications for treatment for more detail on oxidative phosphorylation and associated processes.) Acetate groups in the cell bind to carnitine to form acetyl L-carnitine, which can then pass through the mitchondrial membrane. The acetate group is then given up and L-carnitine passes back through the mitochondrial membrane into the cell in order to pick up another molecule of acetate. Using the car analogy, carnitine is like the nozzle on the fuel pump that delivers fuel into the tank of your car where it is needed.
Carnitine can be made in both the liver and the kidney from cysteine and methionine (both amino acids in animal protein) and requires iron and vitamin C for its synthesis. In muscle meats L-carnitine makes up 0.1% of dry matter. There is very little carnitine in plant derived foods, which may partly explain why vegetarianism seems to be a risk factor for chronic fatigue.
A typical sort of dose to treat problems associated with poor mitochondrial function is 2 grams a day. Studies have shown it is highly effective in ischaemic heart disease. It has also been trialled in the treatment of chronic fatigue syndrome and a precis of results of that trial are as follows:[1]
