“…They are either presently at a very early phase of clinical trial, with no clear outcome or they have yielded mixed results after trial. 30 These treatments vary greatly in approach, for example, changing the phenotype of neurons (gene therapy, introduction of viral vectors), 31 introducing trophic factors that increase neuronal survival (eg, glial cell line-derived neurotrophic factor), 32 stimulating neurogenesis, 33 increasing patient exercise programs, 34 and finally, changing dietary intake, for instance, using antioxidants (eg, coenzyme Q10), fish oil, and vitamin E. 35 Light therapy, specifically low-level laser therapy of red to infrared light, is an emerging, putative neuroprotective treatment that, as with the aforementioned treatments, is showing promise at the basic science level. It awaits rigorous exploration at the clinical level for Parkinson's disease, but given its novel mode of application (see below; "What is light therapy and how does it offer neuroprotection"), we are very hopeful of positive outcomes for many patients.…”