Low levels of the carnitine compound acylcarnitine in the blood or muscles of people with CFIDS/FMS have been found by two different research centers.9 Carnitine plays many roles in the body. It has the critical function of preventing the mitochondria from being shut down when the system backs up. It does this by keeping a substance called acetyl coenzyme A from building up and shutting down the TCA cycle and the electron transport system, the cell's effective energy-burning systems. Also, without sufficient carnitine, the body cannot burn fat (and, in fact, makes excess fat), resulting in large weight gains.
L-Carnitine is a naturally occurring form of carnitine that is only found in animal flesh. Beef is high in carnitine. Carnitine can also be synthesized in the body. This process requires adequate amounts of the amino acid lysine, which is low in rice-based vegetarian diets (which also have no carnitine).10 I suspect that the real reason many CFIDS patients who take lysine to prevent herpes outbreaks see their symptoms improve may be that this increases the body's carnitine production.
In my experience, and that of other clinicians, taking supplemental L-carnitine has not been very helpful, and D-L-carnitine can actually worsen symptoms.11 Taking 500 milligrams of acetyl L-carnitine 500 milligrams 2-3 times a day, however, can be very helpful. It has no side effects except for its cost, usually $1.00 for 1,000 milligrams. Adding 500 to 1,000 milligrams of L-lysine, which is cheaper, can decrease the amount of acetyl-L-carnitine you need to take by helping your body to make its own carnitine. The body also requires vitamin C (I recommend 200+ milligrams a day) and B-complex vitamins to make carnitine.12 Lysine, B Complex, and Vitamin C are all present in a good multivitamin powder. I suspect that most people can lower their dose of acetyl-L-carnitine after 12-16 weeks—for example, to 500 milligrams a day-or even stop it. Any brand is fine as long as it is pure acetyl-L-carnitine.
- 9. A. V. Plioplys and S. Plioplys, "Amantadine and L-Carnitine Treatment of Chronic Fatigue Syndrome," Neuropsychobiology 35 (1) (1997): 16-23. H. Kuratsune, K. Yamaguti, M. Takahashi, et al., “Acylcarnitine Deficiency in Chronic Fatigue Syndrome,” Clinical Infectious Disease 18 (3 Supplement 1) (January 1994): S62–S67.
- 10. V. Tanphaichitr and P. Leelahagul, "Carnitine Metabolism and Human Carnitine Deficiency," review article, Nutrition 9 (3) (May-June 1993): 246-252.
- 11. R.E. Keith, "Symptoms of Carnitine Like Deficiency in a Trained Runner Taking DL-Carnitine Supplements," letter, Journal of the American Medical Association 255 (9) (7 March 1986): 1137.
- 12. H.E.F. Davies, et al., "Ascorbic Acid and Carnitine in Man," Nutrition Reports International 36 (1987): 941.