Once upon a time, Parkinson's Disease was believed to be a purely neurological problem, caused by dopamine producing cell death in a bean sized part of the brain called the Substantia Nigra. We now know that this neurodegeneration is not necessarily casual, but an effect resulting from more systemic issues, which become worse over a sustained period of years prior to diagnosis. Today, it is widely accepted that problems with the gut and digestive system, including nutritional deficits - due to resulting impaired absorption, are not only integral to PD, but are also likely to play major roles in the true causal factors.