The very old may benefit from L-carnitine

NEW YORK (Reuters Health) - The dietary supplement L-carnitine can lessen fatigue and boost mental function in very old people, Italian researchers report.

Study participants given L-carnitine also experienced significant increases in muscle mass and reductions in fat mass, Dr. Mariano Malaguarnera and colleagues from the University of Catania report in the December issue of the American Journal of Clinical nutrition.

L-carnitine helps cells to produce energy from fat. The highest concentrations of the molecule are found in parts of the body with high energy demands, such as the skeletal muscles and the heart. Overall concentrations of L-carnitine decline after age 70.

To determine if supplementation with L-carnitine might improve energy levels in people 100 and older, Malaguarnera's team randomized 66 male and female centenarians to 2 grams of L-carnitine or placebo daily for six months.

Cholesterol levels fell significantly among the individuals taking the supplement, they report. L-carnitine takers also gained 3.8 kilograms (8.4 pounds) of muscle mass, on average, and lost 1.8 kg (4 pounds) of fat mass. People given L-carnitine were also able to walk 4 meters (13 feet) further during a 6-minute walking test after treatment than those given placebo.

Study participants in the L-carnitine group also reported significant reductions in mental, physical and overall fatigue, while placebo treatment had no effect on fatigue. The individuals who took the supplement also scored higher on a test of mental function after treatment, while there was no change in the placebo group.

The supplement was well tolerated by study participants, the researchers report, with no serious side effects.

SOURCE: American Journal of Clinical Nutrition, December 2007.