Q. Can co-enzyme Q10 prevent Parkinson's disease?

A. Parkinson's disease is characterized by a progressive deterioration of motor and mental abilities due to a decrease in the number of dopamine-producing nerve cells in the brain.

Dopamine is crucial to human movement. Symptoms of Parkinson's disease include tremors, stiffness, slow movement, poor coordination and problems with balance. Dementia and depression can occur in the later stages.

Co-enzyme Q10 (CoQ) is naturally found in our body's cells. CoQ helps our cells produce energy.

The relationship between co-enzyme Q10 and Parkinson's is still under study, but looks promising.

Several years ago, researchers determined that there is less CoQ in the cells of Parkinson's patients than normal. Animal studies have indicated that CoQ may protect the part of the brain responsible for Parkinson's disease.

Researchers at the University of California-San Diego studied 80 people with early stage Parkinson's disease. Participants received either a placebo or CoQ (at 300, 600, or 1,200 milligrams dosage) plus 1,200 international units of vitamin E daily.

Those receiving the most CoQ showed the least disease progression over 16 months. The greatest benefits were seen in activities of daily living such as feeding, dressing, bathing, and walking. No adverse effects were reported.

This year, the same researchers plan a longer study with more participants.

Since 1,200 mg of CoQ was the largest and most effective dose in the previous study, participants will receive either 1,200 or 2,400 mg of CoQ daily. There will also be a group receiving a placebo pill.

Since this study will also be of longer duration than the previous study, it should be able to answer questions about the longer-term effects of large doses of co-enzyme Q10 in Parkinson's disease.

The bottom line is that it is too early to recommend coenzyme Q10 for all people with Parkinson's disease. For those in the early stages of the disease, check with your your neurologist about the possibility of taking co-enzyme Q10 and vitamin E for a year to 16 months. We don't know the effects of taking CoQ for longer periods or in larger doses. We also don't know if it helps those in the later stages of the disease. With the new research that is on the horizon, we will one day have these answers.

Amy Tousman is a registered dietitian with the Health Education Center of Straub Clinic and Hospital. Hawai'i experts in traditional medicine, naturopathic medicine and diet take turns writing the Prescriptions column. Send your questions to: Prescriptions, Island Life, The Advertiser, P.O. Box 3110, Honolulu, HI 96802; fax 535-8170; or islandlife@honoluluadvertiser.com. This column is not intended to provide medical advice.