From The December 2001 Issue of Nutrition Science News

L-Carnitine Aids Circulation in Legs

Results of a new study indicate that L-carnitine may improve exercise ability in people with poor circulation in their legs. Peripheral arterial disease impairs circulation and can lead to claudication—a sharp leg pain that limits exercise.

In a study conducted by William Hiatt, M.D., of the University of Colorado Health Sciences Center in Denver, 155 Americans and Russians age 40 to 80 were randomly selected to take either 2 g/day L-carnitine or placebo for six months. To assess their walking ability, the participants were tested on a graded treadmill at 2 mph. The grade began level and increased 2 percent every two minutes. Subjects walked until leg pain became intense.

Participants also filled out a questionnaire to determine how they perceived their walking ability and their overall functioning. Nearly all the participants were Caucasian; more than 90 percent were previous or current smokers; about half were taking other medications.

After six months, the 82 who took L-carnitine walked 39 percent longer compared with a 14 percent improvement in the place- bo group. In addition, those taking the supplement experienced a self-declared boost in overall health and vitality. There were no reported side effects.

L-carnitine contributes to energy production within muscle cells, and supplementation increases the energy available to skeletal muscle. In addition, Hiatt speculates, the supplement may also improve blood vessel integrity.

—American Journal of Medicine
2001;110:616-22.