A relationship between increased caffeine intake and lower risk for Parkinson's disease has been repeatedly confirmed. A more recent study that specifically focused on the effects of caffeine in individuals with a mutation in the leucine-rich repeat kinase 2 (LRRK2) gene found that that group in particular may benefit from caffeine-related therapies. Those with Parkinson's disease have been shown to have lower levels of caffeine than those without; individuals with LRRK2 mutations had levels even lower than those of other patients with Parkinson's disease.
Levels of caffeine and nine of its metabolites have been shown to be significantly lower in individuals with Parkinson's disease compared with those without. As a result, some researchers have suggested that those findings may represent viable biomarkers for the identification of early Parkinson's disease.
The effects of caffeine on motor symptoms in patients with Parkinson's disease is less clear. Although some findings have suggested that caffeine intake improved gait and other concerns, caffeine given at a dose equivalent of three cups of coffee a day failed to improve motor symptoms. Although caffeine may aid in the risk for and progression of Parkinson's disease, levodopa remains recommended as the first-line treatment for motor symptoms.
Read more about Parkinson's disease.