Do doctors have any suggestions on how to prevent parkinson's disease?

Not really: Not really, there have been anecdotal reports of antioxidants, co-enzyme q and even nicotine (yes, cigarette smoking) retarding the development, but nothing engraved in stone and most studies show a possible slowing at best. The key to Parkinson's prevention and cure will be stem cells.

No.: Cause and cure for parkinson's disease unknown. Parkinsonism (diseases resembling parkinson's) may be triggered by chemicals (e.g. Mptp) or repeat head trauma (example boxer muhammad ali). Anti-oxidants (turmeric, peppers etc) are rumored to be beneficial but no proof there.

Maybe soon: A recent study has raised questions that this may be caused by an infection from prions, the small particles which cause creutzfeldt-jakob disease. If this indeed proves true, we may find some amazing breakthroughs.